WorldWideScience

Sample records for time waiting period

  1. Wait times in Canada.

    Science.gov (United States)

    MacKinnon, Janice Christine

    2017-07-01

    A significant barrier to accessing healthcare in Canada is long waiting lists, which can be linked to the way that Medicare was structured. After significant pressure, provincial governments began to address wait times. An example of a successful strategy to reduce wait times for elective surgery is the Saskatchewan Surgical Initiative, which saw wait times in the province change from being among the longest in Canada to the shortest.

  2. Handgun waiting periods reduce gun deaths.

    Science.gov (United States)

    Luca, Michael; Malhotra, Deepak; Poliquin, Christopher

    2017-11-14

    Handgun waiting periods are laws that impose a delay between the initiation of a purchase and final acquisition of a firearm. We show that waiting periods, which create a "cooling off" period among buyers, significantly reduce the incidence of gun violence. We estimate the impact of waiting periods on gun deaths, exploiting all changes to state-level policies in the Unites States since 1970. We find that waiting periods reduce gun homicides by roughly 17%. We provide further support for the causal impact of waiting periods on homicides by exploiting a natural experiment resulting from a federal law in 1994 that imposed a temporary waiting period on a subset of states. Copyright © 2017 the Author(s). Published by PNAS.

  3. Bell inequalities and waiting times

    Energy Technology Data Exchange (ETDEWEB)

    Poeltl, Christina; Governale, Michele [School of Chemical and Physical Sciences and MacDiarmid Institute for Advanced Materials and Nanotechnology, Victoria University of Wellington, PO Box 600, Wellington 6140 (New Zealand)

    2015-07-01

    We propose a Bell test based on waiting time distributions for spin entangled electron pairs, which are generated and split in mesoscopic Coulomb blockade structures, denoted as entanglers. These systems have the advantage that quantum point contacts enable a time resolved observation of the electrons occupying the system, which gives access to quantities such as full counting statistics and waiting time distributions. We use the partial waiting times to define a CHSH-Bell test, which is a purely electronic analogue of the test used in quantum optics. After the introduction of the Bell inequality we discuss the findings on the two examples of a double quantum dot and a triple quantum dot. This Bell test allows the exclusion of irrelevant tunnel processes from the statistics normally used for the Bell correlations. This can improve the parameter range for which a violation of the Bell inequality can be measured significantly.

  4. Time while waiting: patients' experiences of scheduled surgery.

    Science.gov (United States)

    Carr, Tracey; Teucher, Ulrich C; Casson, Alan G

    2014-12-01

    Research on patients' experiences of wait time for scheduled surgery has centered predominantly on the relative tolerability of perceived wait time and impacts on quality of life. We explored patients' experiences of time while waiting for three types of surgery with varied wait times--hip or knee replacement, shoulder surgery, and cardiac surgery. Thirty-two patients were recruited by their surgeons. We asked participants about their perceptions of time while waiting in two separate interviews. Using interpretative phenomenological analysis (IPA), we discovered connections between participant suffering, meaningfulness of time, and agency over the waiting period and the lived duration of time experience. Our findings reveal that chronological duration is not necessarily the most relevant consideration in determining the quality of waiting experience. Those findings helped us create a conceptual framework for lived wait time. We suggest that clinicians and policy makers consider the complexity of wait time experience to enhance preoperative patient care. © The Author(s) 2014.

  5. 46 CFR 9.10 - Waiting time.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Waiting time. 9.10 Section 9.10 Shipping COAST GUARD... § 9.10 Waiting time. The same construction should be given the act when charging for waiting time as... for duty the waiting time amounts to at least one hour. ...

  6. Waiting time guarantee - an update

    DEFF Research Database (Denmark)

    Socha, Karolina; Bech, Mickael

    2008-01-01

    The rule of extended free choice of hospital, in force since 2002, provides patients with an option to choose a private hospital if the public system is unable to provide a treatment within the guaranteed waiting time of one month. In June 2008 the Government declared in their yearly budget agree...

  7. Advertising Emergency Department Wait Times

    OpenAIRE

    Weiner, Scott G

    2013-01-01

    Advertising emergency department (ED) wait times has become a common practice in the United States. Proponents of this practice state that it is a powerful marketing strategy that can help steer patients to the ED. Opponents worry about the risk to the public health that arises from a patient with an emergent condition self-triaging to a further hospital, problems with inaccuracy and lack of standard definition of the reported time, and directing lower acuity patients to the higher cost ED se...

  8. Advertising emergency department wait times.

    Science.gov (United States)

    Weiner, Scott G

    2013-03-01

    Advertising emergency department (ED) wait times has become a common practice in the United States. Proponents of this practice state that it is a powerful marketing strategy that can help steer patients to the ED. Opponents worry about the risk to the public health that arises from a patient with an emergent condition self-triaging to a further hospital, problems with inaccuracy and lack of standard definition of the reported time, and directing lower acuity patients to the higher cost ED setting instead to primary care. Three sample cases demonstrating the pitfalls of advertising ED wait times are discussed. Given the lack of rigorous evidence supporting the practice and potential adverse effects to the public health, caution about its use is advised.

  9. Advertising Emergency Department Wait Times

    Science.gov (United States)

    Weiner, Scott G.

    2013-01-01

    Advertising emergency department (ED) wait times has become a common practice in the United States. Proponents of this practice state that it is a powerful marketing strategy that can help steer patients to the ED. Opponents worry about the risk to the public health that arises from a patient with an emergent condition self-triaging to a further hospital, problems with inaccuracy and lack of standard definition of the reported time, and directing lower acuity patients to the higher cost ED setting instead to primary care. Three sample cases demonstrating the pitfalls of advertising ED wait times are discussed. Given the lack of rigorous evidence supporting the practice and potential adverse effects to the public health, caution about its use is advised. PMID:23599836

  10. Advertising Emergency Department Wait Times

    Directory of Open Access Journals (Sweden)

    Scott G. Weiner

    2013-03-01

    Full Text Available Advertising emergency department (ED wait times has become a common practice in the UnitedStates. Proponents of this practice state that it is a powerful marketing strategy that can help steerpatients to the ED. Opponents worry about the risk to the public health that arises from a patient withan emergent condition self-triaging to a further hospital, problems with inaccuracy and lack of standarddefinition of the reported time, and directing lower acuity patients to the higher cost ED setting insteadto primary care. Three sample cases demonstrating the pitfalls of advertising ED wait times arediscussed. Given the lack of rigorous evidence supporting the practice and potential adverse effects tothe public health, caution about its use is advised

  11. Two Effective Ways to Implement Wait Time. A Symposium on Wait Time.

    Science.gov (United States)

    Swift, J. Nathan; And Others

    The effects of instructional guides and a wait time feedback device (called a "Wait Timer") on the classroom interaction of middle school science teachers are examined. The Wait Timer, an unobtrusive indicator of wait time, is an automatic device that activates a light when a person speaks. The duration of the light at the end of a…

  12. Queues with waiting time dependent service

    DEFF Research Database (Denmark)

    Bekker, R.; Koole, G. M.; Nielsen, Bo Friis

    2011-01-01

    Motivated by service levels in terms of the waiting-time distribution seen, for instance, in call centers, we consider two models for systems with a service discipline that depends on the waiting time. The first model deals with a single server that continuously adapts its service rate based...... derive steady-state waiting-time distributions for both models. The results are illustrated with numerical examples....... on the waiting time of the first customer in line. In the second model, one queue is served by a primary server which is supplemented by a secondary server when the waiting of the first customer in line exceeds a threshold. Using level crossings for the waiting-time process of the first customer in line, we...

  13. Can We Predict Patient Wait Time?

    Science.gov (United States)

    Pianykh, Oleg S; Rosenthal, Daniel I

    2015-10-01

    The importance of patient wait-time management and predictability can hardly be overestimated: For most hospitals, it is the patient queues that drive and define every bit of clinical workflow. The objective of this work was to study the predictability of patient wait time and identify its most influential predictors. To solve this problem, we developed a comprehensive list of 25 wait-related parameters, suggested in earlier work and observed in our own experiments. All parameters were chosen as derivable from a typical Hospital Information System dataset. The parameters were fed into several time-predicting models, and the best parameter subsets, discovered through exhaustive model search, were applied to a large sample of actual patient wait data. We were able to discover the most efficient wait-time prediction factors and models, such as the line-size models introduced in this work. Moreover, these models proved to be equally accurate and computationally efficient. Finally, the selected models were implemented in our patient waiting areas, displaying predicted wait times on the monitors located at the front desks. The limitations of these models are also discussed. Optimal regression models based on wait-line sizes can provide accurate and efficient predictions for patient wait time. Copyright © 2015 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  14. Improving Patient Satisfaction with Waiting Time

    Science.gov (United States)

    Eilers, Gayleen M.

    2004-01-01

    Waiting times are a significant component of patient satisfaction. A patient satisfaction survey performed in the author's health center showed that students rated waiting time lowest of the listed categories--A ratings of 58% overall, 63% for scheduled appointments, and 41% for the walk-in clinic. The center used a quality improvement process and…

  15. Factors of Perceived Waiting Time and Implications on Passengers’ Satisfaction with Waiting Time

    Directory of Open Access Journals (Sweden)

    Shumin Feng

    2016-04-01

    Full Text Available In order to explore the influence factors on perceived waiting time, a multiple linear regression model has been used to quantitatively describe the relationship between perceived waiting time and various factors. The model is established with 234 data, which is surveyed with questionnaire at three stops in Harbin, China. The results show that several certain factors (“trip purpose - where to”, “presence of a companion - whether one has a companion or not”, “having a timing device - whether one has a timing device or not”, “riding frequency - how many times one takes one line per week” and “waiting behaviour - what one does while waiting for a bus” have significant influence on perceived waiting time, which confirms previous findings and supports transferability of results. The significance of “waiting mood - howabout the mood while waiting for a bus” and “reserved waiting time - how long one will wait” are confirmed for the first time in this study. In contrast to previous studies, “waiting time interval - for how long in one day” is a negative variable and socioeconomic variables are non-significant. And it is found that the relationship between perceived waiting time and passengers’ satisfaction with the waiting time follows a decreasing exponential distribution. With this model, the variation trend of the section, where passenger satisfaction value is larger than 0 is obviously steeper than the section smaller than 0. Such result proves that passenger mood with short waiting time is more sensitive than with longer waiting time. And the borderline perceived waiting time, distinguishing satisfied from dissatisfied passengers is proven to be 7.87 minutes when assignment interval of satisfaction is (-25.25], when satisfaction is positive (larger than 0, the accuracy being 70.30%, while the accuracy is 82.71% fornegative satisfaction (less than 0.

  16. Economic performance of lactating dairy cows submitted for first service timed artificial insemination after a voluntary waiting period of 60 or 88 days.

    Science.gov (United States)

    Stangaferro, M L; Wijma, R; Masello, M; Thomas, Mark J; Giordano, J O

    2018-05-23

    The objective of this study was to evaluate the economic performance of dairy cows managed with a voluntary waiting period (VWP) of 60 or 88 d. A secondary objective was estimating variation in cash flow under different input pricing scenarios through stochastic Monte Carlo simulations. Lactating Holstein cows from 3 commercial farms were blocked by parity group and total milk yield in their previous lactation and then randomly assigned to a VWP of 60 (VWP60; n = 1,352) or 88 d (VWP88; n = 1,359). All cows received timed-artificial insemination (TAI) for first service after synchronization of ovulation with the Double-Ovsynch protocol. For second and greater services, cows received artificial insemination (AI) after detection of estrus or the Ovsynch protocol initiated 32 ± 3 d after AI. Two analyses were performed: (1) cash flow per cow for the calving interval of the experimental lactation and (2) cash flow per slot occupied by each cow enrolled in the experiment for an 18-mo period after calving in the experimental lactation. Extending the VWP from 60 to 88 d delayed time to pregnancy during lactation (~20 d) and increased the risk of leaving the herd for multiparous cows (hazard ratio = 1.21). As a result, a smaller proportion of multiparous cows calved again and had a subsequent lactation (-6%). The shift in time to pregnancy combined with the herd exit dynamics resulted in longer lactation length for primiparous (22 d) but not multiparous cows. Longer lactations led to greater milk income over feed cost and a tendency for greater cash flow during the experimental lactation for primiparous but not multiparous cows in the VWP88 group. On the other hand, profitability per slot for the 18-mo period was numerically greater ($68 slot/18 mo) for primiparous cows but numerically reduced (-$85 slot/18 mo) for multiparous cows in the VWP88 treatment. For primiparous cows most of the difference in cash flow was explained by replacement cost, whereas for multiparous

  17. Stochastic nature of series of waiting times

    Science.gov (United States)

    Anvari, Mehrnaz; Aghamohammadi, Cina; Dashti-Naserabadi, H.; Salehi, E.; Behjat, E.; Qorbani, M.; Khazaei Nezhad, M.; Zirak, M.; Hadjihosseini, Ali; Peinke, Joachim; Tabar, M. Reza Rahimi

    2013-06-01

    Although fluctuations in the waiting time series have been studied for a long time, some important issues such as its long-range memory and its stochastic features in the presence of nonstationarity have so far remained unstudied. Here we find that the “waiting times” series for a given increment level have long-range correlations with Hurst exponents belonging to the interval 1/2waiting time distribution. We find that the logarithmic difference of waiting times series has a short-range correlation, and then we study its stochastic nature using the Markovian method and determine the corresponding Kramers-Moyal coefficients. As an example, we analyze the velocity fluctuations in high Reynolds number turbulence and determine the level dependence of Markov time scales, as well as the drift and diffusion coefficients. We show that the waiting time distributions exhibit power law tails, and we were able to model the distribution with a continuous time random walk.

  18. WAITING TIME IN THE WAITING ROOM IN FAMILY PRACTICE AND PATIENT SATISFACTION

    Directory of Open Access Journals (Sweden)

    Janko Kersnik

    2001-05-01

    Full Text Available Background: Appointment system shortens the waiting time in the waiting room for the patient and allows better use of time for the doctor. We wanted to examine how long patients are willing to wait in the waiting room, how long they waited at the last visit, patient satisfaction with the last visit, the satisfaction with the length of waiting in the past 12 months and the overall patient satisfaction score for the last 12 months. Appointment system proved to be effective means of organising practice time. Waiting time in the waiting room with appointment system was considerably shorter (mean 18.5 minutes as compared to the waiting time in the practices without appointment system (mean 55.4 minutes, the fact which is reflected also in higher satisfaction with waiting in the waiting room in the past 12 months. Three quarters of patients in practices with appointment system waited standard 20 minutes or less, as opposed to the other practices where only one quarter of patients waited 20 minutes or less.Conclusions: The overall satisfaction with the doctor with the appointment system does not differ in both types of practices. The patients from practices with appointment system evaluated better possibility to get an appointment to suit the patients, but worse help of the doctors’ staff, possibility to get through to the office by phone, the length of time during the consultation and the doctors’ thoroughness.

  19. Effect of emergency physician burnout on patient waiting times.

    Science.gov (United States)

    De Stefano, Carla; Philippon, Anne-Laure; Krastinova, Evguenia; Hausfater, Pierre; Riou, Bruno; Adnet, Frederic; Freund, Yonathan

    2018-04-01

    Burnout is common in emergency physicians. This syndrome may negatively affect patient care and alter work productivity. We seek to assess whether burnout of emergency physicians impacts waiting times in the emergency department. Prospective study in an academic ED. All patients who visited the main ED for a 4-month period in 2016 were included. Target waiting times are assigned by triage nurse to patients on arrival depending on their severity. The primary endpoint was an exceeded target waiting time for ED patients. All emergency physicians were surveyed by a psychologist to assess their level of burnout using the Maslach Burnout Inventory. We defined the level of burnout of the day in the ED as the mean burnout level of the physicians working that day (8:30 to the 8:30 the next day). A logistic regression model was performed to assess whether burnout level of the day was independently associated with prolonged waiting times, along with previously reported predictors. Target waiting time was exceeded in 7524 patients (59%). Twenty-six emergency physicians were surveyed. Median burnout score was 35 [Interquartile (24-49)]. A burnout level of the day higher than 35 was independently associated with an exceeded target waiting time (adjusted odds ratio 1.54, 95% confidence interval 1.39-1.70), together with previously reported predictors (i.e., day of the week, time of the day, trauma, age and daily census). Burnout of emergency physicians was independently associated with a prolonged waiting time for patients visiting the ED.

  20. Worth the wait? How restaurant waiting time influences customer behavior and revenue

    NARCIS (Netherlands)

    de Vries, J.; Roy, Debjit; De Koster, Rene

    2018-01-01

    In many service industries, customers have to wait for service. When customers have a choice, this waiting may influence their service experience, sojourn time, and ultimately spending, reneging, and return behavior. Not much is known however, about the system-wide impact of waiting on customer

  1. Waiting for Art: The Experience of Real Time in Sculpture

    Directory of Open Access Journals (Sweden)

    Elizabeth Buhe

    2011-05-01

    Full Text Available Why and how does some contemporary art make us wait, and why does the beholder choose to stay? This study seeks to answer this question by exploring what happens to the viewer while waiting in front of a “time sculpture,” a term coined here to mean a three-dimensional artwork that is dynamic over a set period of time. Through an analysis of select works by artists Anish Kapoor, Amelia Whitelaw, Michael Sailstorfer, and Roman Signer, the article posits that while in front of these time sculptures, the viewer experiences an anxiety of waiting and temporal confusion that glues him to the spot. Ultimately, by drawing upon Henri Bergson’s concept of duration, the essay suggests that the viewership of time sculpture allows for a heightened state of perception. Normal 0 false false false EN-US X-NONE X-NONE

  2. The Psychosocial Influences of Waiting Periods on Patients Undergoing Endoscopic Submucosal Dissection.

    Science.gov (United States)

    Nagao, Noriko; Tsuchiya, Aya; Ando, Sae; Arita, Mizue; Toyonaga, Takashi; Miyawaki, Ikuko

    This study aimed to clarify psychosocial influences of waiting periods on patients undergoing endoscopic submucosal dissection for cancer at an advanced medical care facility in Japan. Subjects were consenting patients hospitalized from 2009 to 2010. Qualitative and quantitative data were gathered about patients' characteristics, disease and stage, and waiting period. Qualitative content analysis was used to analyze free statements and interview data. Subjects included 154 patients with an average wait period of 46.28 days for admission. Qualitative analysis revealed the following wait period perceptions. For calmness, results indicated (1) no anxiety, (2) relief based on doctors' positive judgment, (3) whatever happens/no choice, and (4) trust in doctor. For uneasiness, perceptions included (1) the sooner, the better/eagerly waiting, (2) anxiety and concern, and (3) emotional instability. Four waiting period coping types were identified: (1) making phone inquiries, (2) busy and forgot about the medical procedure, (3) relief from anxiety, and (4) unable to function well in daily life. Patients need to be educated about cancer progression and provided an estimated wait time. They also require more information about how to manage daily life such as monitoring factors from the nursing domain including physical condition, digestive symptoms, diet, and exercise.

  3. Sustainability: orthopaedic surgery wait time management strategies.

    Science.gov (United States)

    Amar, Claudia; Pomey, Marie-Pascale; SanMartin, Claudia; De Coster, Carolyn; Noseworthy, Tom

    2015-01-01

    The purpose of this paper is to examine Canadian organizational and systemic factors that made it possible to keep wait times within federally established limits for at least 18 months. The research design is a multiple cases study. The paper selected three cases: Case 1 - staff were able to maintain compliance with requirements for more than 18 months; Case 2 - staff were able to meet requirements for 18 months, but unable to sustain this level; Case 3 - staff were never able to meet the requirements. For each case the authors interviewed persons involved in the strategies and collected documents. The paper analysed systemic and organizational-level factors; including governance and leadership, culture, resources, methods and tools. Findings indicate that the hospital that was able to maintain compliance with the wait time requirements had specific characteristics: an exclusive mandate to do only hip and knee replacement surgery; motivated staff who were not distracted by other concerns; and a strong team spirit. The authors' research highlights an important gradient between three cases regarding the factors that sustain waiting times. The paper show that the hospital factory model seems attractive in a super-specialized surgery context. However, patients are selected for simple surgeries, without complications, and so this cannot be considered a unique model.

  4. Waiting time distribution in M/D/1 queueing systems

    DEFF Research Database (Denmark)

    Iversen, Villy Bæk; Staalhagen, Lars

    1999-01-01

    The well-known formula for the waiting time distribution of M/D/1 queueing systems is numerically unsuitable when the load is close to 1.0 and/or the results for a large waiting time are required. An algorithm for any load and waiting time is presented, based on the state probabilities of M/D/1...

  5. Outpatient waiting time in Jos University Teaching Hospital ...

    African Journals Online (AJOL)

    Problem Long waiting time for services has been identified as a reason people avoid presenting to for care in African countries. Design Examination of causes for long outpatient waiting time and the effect of measures to reduce waiting time. Setting Outpatient department of the Jos University Teaching Hospital.

  6. Estimating bus passenger waiting times from incomplete bus arrivals data

    OpenAIRE

    McLeod, F.N.

    2007-01-01

    This paper considers the problem of estimating bus passenger waiting times at bus stops using incomplete bus arrivals data. This is of importance to bus operators and regulators as passenger waiting time is a key performance measure. Average waiting times are usually estimated from bus headways, that is, time gaps between buses. It is both time-consuming and expensive to measure bus arrival times manually so methods using automatic vehicle location systems are attractive; however, these syste...

  7. Third degree waiting time discrimination: optimal allocation of a public sector healthcare treatment under rationing by waiting.

    Science.gov (United States)

    Gravelle, Hugh; Siciliani, Luigi

    2009-08-01

    In many public healthcare systems treatments are rationed by waiting time. We examine the optimal allocation of a fixed supply of a given treatment between different groups of patients. Even in the absence of any distributional aims, welfare is increased by third degree waiting time discrimination: setting different waiting times for different groups waiting for the same treatment. Because waiting time imposes dead weight losses on patients, lower waiting times should be offered to groups with higher marginal waiting time costs and with less elastic demand for the treatment.

  8. SU-F-P-20: Predicting Waiting Times in Radiation Oncology Using Machine Learning

    International Nuclear Information System (INIS)

    Joseph, A; Herrera, D; Hijal, T; Kildea, J; Hendren, L; Leung, A; Wainberg, J; Sawaf, M; Gorshkov, M; Maglieri, R; Keshavarz, M

    2016-01-01

    Purpose: Waiting times remain one of the most vexing patient satisfaction challenges facing healthcare. Waiting time uncertainty can cause patients, who are already sick or in pain, to worry about when they will receive the care they need. These waiting periods are often difficult for staff to predict and only rough estimates are typically provided based on personal experience. This level of uncertainty leaves most patients unable to plan their calendar, making the waiting experience uncomfortable, even painful. In the present era of electronic health records (EHRs), waiting times need not be so uncertain. Extensive EHRs provide unprecedented amounts of data that can statistically cluster towards representative values when appropriate patient cohorts are selected. Predictive modelling, such as machine learning, is a powerful approach that benefits from large, potentially complex, datasets. The essence of machine learning is to predict future outcomes by learning from previous experience. The application of a machine learning algorithm to waiting time data has the potential to produce personalized waiting time predictions such that the uncertainty may be removed from the patient’s waiting experience. Methods: In radiation oncology, patients typically experience several types of waiting (eg waiting at home for treatment planning, waiting in the waiting room for oncologist appointments and daily waiting in the waiting room for radiotherapy treatments). A daily treatment wait time model is discussed in this report. To develop a prediction model using our large dataset (with more than 100k sample points) a variety of machine learning algorithms from the Python package sklearn were tested. Results: We found that the Random Forest Regressor model provides the best predictions for daily radiotherapy treatment waiting times. Using this model, we achieved a median residual (actual value minus predicted value) of 0.25 minutes and a standard deviation residual of 6.5 minutes

  9. SU-F-P-20: Predicting Waiting Times in Radiation Oncology Using Machine Learning

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, A; Herrera, D; Hijal, T; Kildea, J [McGill University Health Centre, Montreal, Quebec (Canada); Hendren, L; Leung, A; Wainberg, J; Sawaf, M; Gorshkov, M; Maglieri, R; Keshavarz, M [McGill University, Montreal, Quebec (Canada)

    2016-06-15

    Purpose: Waiting times remain one of the most vexing patient satisfaction challenges facing healthcare. Waiting time uncertainty can cause patients, who are already sick or in pain, to worry about when they will receive the care they need. These waiting periods are often difficult for staff to predict and only rough estimates are typically provided based on personal experience. This level of uncertainty leaves most patients unable to plan their calendar, making the waiting experience uncomfortable, even painful. In the present era of electronic health records (EHRs), waiting times need not be so uncertain. Extensive EHRs provide unprecedented amounts of data that can statistically cluster towards representative values when appropriate patient cohorts are selected. Predictive modelling, such as machine learning, is a powerful approach that benefits from large, potentially complex, datasets. The essence of machine learning is to predict future outcomes by learning from previous experience. The application of a machine learning algorithm to waiting time data has the potential to produce personalized waiting time predictions such that the uncertainty may be removed from the patient’s waiting experience. Methods: In radiation oncology, patients typically experience several types of waiting (eg waiting at home for treatment planning, waiting in the waiting room for oncologist appointments and daily waiting in the waiting room for radiotherapy treatments). A daily treatment wait time model is discussed in this report. To develop a prediction model using our large dataset (with more than 100k sample points) a variety of machine learning algorithms from the Python package sklearn were tested. Results: We found that the Random Forest Regressor model provides the best predictions for daily radiotherapy treatment waiting times. Using this model, we achieved a median residual (actual value minus predicted value) of 0.25 minutes and a standard deviation residual of 6.5 minutes

  10. Should I stay or should I go? Hospital emergency department waiting times and demand.

    Science.gov (United States)

    Sivey, Peter

    2018-03-01

    In the absence of the price mechanism, hospital emergency departments rely on waiting times, alongside prioritisation mechanisms, to restrain demand and clear the market. This paper estimates by how much the number of treatments demanded is reduced by a higher waiting time. I use variation in waiting times for low-urgency patients caused by rare and resource-intensive high-urgency patients to estimate the relationship. I find that when waiting times are higher, more low-urgency patients are deterred from treatment and leave the hospital during the waiting period without being treated. The waiting time elasticity of demand for low-urgency patients is approximately -0.25 and is highest for the lowest-urgency patients. Copyright © 2017 John Wiley & Sons, Ltd.

  11. The Effects of Immigration on NHS Waiting Times

    OpenAIRE

    Giuntella, Osea; Nicodemo, Catia; Vargas-Silva, Carlos

    2015-01-01

    This paper analyses the effects of immigration on waiting times in the National Health Service (NHS) in England. Linking administrative records from the Hospital Episode Statistics (2003-2012) with immigration data drawn from the UK Labour Force Survey, we find that immigration reduced waiting times for outpatient referrals and did not have significant effects on waiting times in Accident and Emergency (A&E) and elective care. These results are explained by the fact that immigration increases...

  12. TSA Security Checkpoint Wait Times – API (PMIS)

    Data.gov (United States)

    Department of Homeland Security — TSA operational data including: Airport wait time (hourly) data Airport throughput (hourly) data Prohibited item (hourly) data Monthly Objectives Report (MOR) data...

  13. Norwegian Priority Setting in Practice – an Analysis of Waiting Time Patterns Across Medical Disciplines

    Directory of Open Access Journals (Sweden)

    Jurgita Januleviciute Gangstøe

    2016-06-01

    Full Text Available Background: Different strategies for addressing the challenge of prioritizing elective patients efficiently and fairly have been introduced in Norway. In the time period studied, there were three possible outcomes for elective patients that had been through the process of priority setting: (i high priority with assigned individual maximum waiting time; (ii low priority without a maximum waiting time; and (iii refusal (not in need for specialized services. We study variation in priority status and waiting time of the first two groups across different medical disciplines. Methods: Data was extracted from the Norwegian Patient Register (NPR and contains information on elective referrals to 41 hospitals in the Western Norway Regional Health Authority in 2010. The hospital practice across different specialties was measured by patient priority status and waiting times. The distributions of assigned maximum waiting times and the actual ones were analyzed using standard Kernel density estimation. The perspective of the planning process was studied by measuring the time interval between the actual start of healthcare and the maximum waiting time. Results: Considerable variation was found across medical specialties concerning proportion of priority patients and their maximum waiting times. The degree of differentiation in terms of maximum waiting times also varied by medical discipline. We found that the actual waiting time was very close to the assigned maximum waiting time. Furthermore, there was no clear correspondence between the actual waiting time for patients and their priority status. Conclusion: Variations across medical disciplines are often interpreted as differences in clinical judgment and capacity. Alternatively they primarily reflect differences in patient characteristics, patient case-mix, as well as capacity. One hypothesis for further research is that the introduction of maximum waiting times may have contributed to push the actual

  14. Electron Waiting Times of a Cooper Pair Splitter

    Science.gov (United States)

    Walldorf, Nicklas; Padurariu, Ciprian; Jauho, Antti-Pekka; Flindt, Christian

    2018-02-01

    Electron waiting times are an important concept in the analysis of quantum transport in nanoscale conductors. Here we show that the statistics of electron waiting times can be used to characterize Cooper pair splitters that create spatially separated spin-entangled electrons. A short waiting time between electrons tunneling into different leads is associated with the fast emission of a split Cooper pair, while long waiting times are governed by the slow injection of Cooper pairs from a superconductor. Experimentally, the waiting time distributions can be measured using real-time single-electron detectors in the regime of slow tunneling, where conventional current measurements are demanding. Our work is important for understanding the fundamental transport processes in Cooper pair splitters and the predictions may be verified using current technology.

  15. Electron Waiting Times of a Cooper Pair Splitter

    DEFF Research Database (Denmark)

    Walldorf, Nicklas; Padurariu, Ciprian; Jauho, Antti-Pekka

    2018-01-01

    Electron waiting times are an important concept in the analysis of quantum transport in nanoscale conductors. Here we show that the statistics of electron waiting times can be used to characterize Cooper pair splitters that create spatially separated spin-entangled electrons. A short waiting time...... between electrons tunneling into different leads is associated with the fast emission of a split Cooper pair, while long waiting times are governed by the slow injection of Cooper pairs from a superconductor. Experimentally, the waiting time distributions can be measured using real-time single......-electron detectors in the regime of slow tunneling, where conventional current measurements are demanding. Our work is important for understanding the fundamental transport processes in Cooper pair splitters and the predictions may be verified using current technology....

  16. Moderate alcohol consumption and waiting time to pregnancy

    DEFF Research Database (Denmark)

    Juhl, Mette; Andersen, Anne-Marie Nybo; Grønbaek, Morten

    2001-01-01

    BACKGROUND: Recent research indicates that even a moderate consumption of alcohol in women trying to become pregnant is associated with longer waiting time to pregnancy. The findings, though, are based upon few observations. METHODS: Self-reported data on alcohol intake and waiting time to pregna...

  17. Enhancing outpatient clinics management software by reducing patients’ waiting time

    Directory of Open Access Journals (Sweden)

    Iman Almomani

    2016-11-01

    Full Text Available Summary: The Kingdom of Saudi Arabia (KSA gives great attention to improving the quality of services provided by health care sectors including outpatient clinics. One of the main drawbacks in outpatient clinics is long waiting time for patients—which affects the level of patient satisfaction and the quality of services. This article addresses this problem by studying the Outpatient Management Software (OMS and proposing solutions to reduce waiting times. Many hospitals around the world apply solutions to overcome the problem of long waiting times in outpatient clinics such as hospitals in the USA, China, Sri Lanka, and Taiwan. These clinics have succeeded in reducing wait times by 15%, 78%, 60% and 50%, respectively. Such solutions depend mainly on adding more human resources or changing some business or management policies. The solutions presented in this article reduce waiting times by enhancing the software used to manage outpatient clinics services. Both quantitative and qualitative methods have been used to understand current OMS and examine level of patient’s satisfaction. Five main problems that may cause high or unmeasured waiting time have been identified: appointment type, ticket numbering, doctor late arrival, early arriving patient and patients’ distribution list. These problems have been mapped to the corresponding OMS components. Solutions to the above problems have been introduced and evaluated analytically or by simulation experiments. Evaluation of the results shows a reduction in patient waiting time. When late doctor arrival issues are solved, this can reduce the clinic service time by up to 20%. However, solutions for early arriving patients reduces 53.3% of vital time, 20% of the clinic time and overall 30.3% of the total waiting time. Finally, well patient-distribution lists make improvements by 54.2%. Improvements introduced to the patients’ waiting time will consequently affect patients’ satisfaction and improve

  18. Parental satisfaction with paediatric care, triage and waiting times.

    Science.gov (United States)

    Fitzpatrick, Nicholas; Breen, Daniel T; Taylor, James; Paul, Eldho; Grosvenor, Robert; Heggie, Katrina; Mahar, Patrick D

    2014-04-01

    The present study aims to determine parental and guardian's perceptions of paediatric emergency care and satisfaction with care, waiting times and triage category in a community ED. A structured questionnaire was provided to parents or guardians of paediatric patients presenting to emergency. The survey evaluated parent perceptions of waiting time, environment/facilities, professionalism and communication skills of staff and overall satisfaction of care. One hundred and thirty-three completed questionnaires were received from parents of paediatric patients. Responses were overall positive with respect to the multiple domains assessed. Parents generally considered waiting times to be appropriate and consistent with triage categories. Overall satisfaction was not significantly different for varying treatment or waiting times. Patients triaged as semi-urgent were of the opinion that waiting times were less appropriate than urgent, less-urgent or non-urgent patients. On the basis of the present study, patient perceptions and overall satisfaction of care does not appear to be primarily influenced by time spent waiting or receiving treatment. Attempts made at the triage process to ensure that semi-urgent patients have reasonable expectations of waiting times might provide an opportunity to improve these patients' expectations and perceptions. © 2014 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

  19. [Influence of waiting time on patient and companion satisfaction].

    Science.gov (United States)

    Fontova-Almató, A; Juvinyà-Canal, D; Suñer-Soler, R

    2015-01-01

    To evaluate patient and companion satisfaction of a hospital Emergency Department and its relationship with waiting time. Prospective, observational study. Hospital de Figueres Emergency Department (Girona, Spain). sociodemographic characteristics, satisfaction level, real and perceived waiting time for triage and being seen by a physician. A total of 285 responses were received from patients and companions. The mean age of the patients and companions (n=257) was 54.6years (SD=18.3). The mean overall satisfaction (n=273) was 7.6 (SD=2.2). Lower perceived waiting time until nurse triage was related to higher overall satisfaction (Spearman rho (ρ)=-0.242, P<.001), and lower perceived waiting time until being seen by physician, with a higher overall satisfaction (ρ=-0.304; P<.001). Users who were informed about estimated waiting time showed higher satisfaction than those who were not informed (P=.001). Perceived waiting time and the information about estimated waiting time determined overall satisfaction. Copyright © 2014 SECA. Published by Elsevier Espana. All rights reserved.

  20. Approaching stationarity: competition between long jumps and long waiting times

    International Nuclear Information System (INIS)

    Dybiec, Bartłomiej

    2010-01-01

    Within the continuous-time random walk (CTRW) scenarios, properties of the overall motion are determined by the waiting time and the jump length distributions. In the decoupled case, with power-law distributed waiting times and jump lengths, the CTRW scenario is asymptotically described by the double (space and time) fractional Fokker–Planck equation. Properties of a system described by such an equation are determined by the subdiffusion parameter and the jump length exponent. Nevertheless, the stationary state is determined solely by the jump length distribution and the potential. The waiting time distribution determines only the rate of convergence to the stationary state. Here, we inspect the competition between long waiting times and long jumps and how this competition is reflected in the way in which a stationary state is reached. In particular, we show that the distance between a time-dependent and a stationary solution changes in time as a double power law

  1. Wait times for gastroenterology consultation in Canada: The patients’ perspective

    Science.gov (United States)

    Paterson, WG; Barkun, AN; Hopman, WM; Leddin, DJ; Paré, P; Petrunia, DM; Sewitch, MJ; Switzer, C; van Zanten, S Veldhuyzen

    2010-01-01

    Long wait times for health care have become a significant issue in Canada. As part of the Canadian Association of Gastroenterology’s Human Resource initiative, a questionnaire was developed to survey patients regarding wait times for initial gastroenterology consultation and its impact. A total of 916 patients in six cities from across Canada completed the questionnaire at the time of initial consultation. Self-reported wait times varied widely, with 26.8% of respondents reporting waiting less than two weeks, 52.4% less than one month, 77.1% less than three months, 12.5% reported waiting longer than six months and 3.6% longer than one year. One-third of patients believed their wait time was too long, with 9% rating their wait time as ‘far too long’; 96.4% believed that maximal wait time should be less than three months, 78.9% believed it should be less than one month and 40.3% believed it should be less than two weeks. Of those working or attending school, 22.6% reported missing at least one day of work or school because of their symptoms in the month before their appointment, and 9.0% reported missing five or more days in the preceding month. A total of 20.2% of respondents reported being very worried about having a serious disease (ie, scored 6 or higher on 7-point Likert scale), and 17.6% and 14.8%, respectively, reported that their symptoms caused major impairment of social functioning and with the activities of daily living. These data suggest that a significant proportion of Canadians with digestive problems are not satisfied with their wait time for gastroenterology consultation. Furthermore, while awaiting consultation, many patients experience an impaired quality of life because of their gastrointestinal symptoms. PMID:20186353

  2. Moderate alcohol consumption and waiting time to pregnancy

    DEFF Research Database (Denmark)

    Juhl, Mette; Andersen, Anne-Marie Nybo; Grønbæk, Morten

    2001-01-01

    BACKGROUND: Recent research indicates that even a moderate consumption of alcohol in women trying to become pregnant is associated with longer waiting time to pregnancy. The findings, though, are based upon few observations. METHODS: Self-reported data on alcohol intake and waiting time...... to pregnancy (0-2, 3-5, 6-12 and >12 months) was used for 39 612 pregnant women, recruited to the Danish National Birth Cohort within the first 24 weeks of pregnancy from 1997 to 2000. Main outcome measures were odds ratios (OR) for a prolonged waiting time to pregnancy according to alcohol intake. RESULTS......: In nulliparous women neither moderate nor high alcohol intake was related with longer waiting time to pregnancy compared with a low intake. In parous women, a modest association was seen only among those with an intake of >14 drinks per week (subfecundity OR 1.3; 95% confidence interval 1.0-1.7). Women who...

  3. Mean Waiting Time and Patients' Satisfaction in GOPD, Federal ...

    African Journals Online (AJOL)

    Mean Waiting Time and Patients' Satisfaction in GOPD, Federal Medical Centre, Owerri. ... Journal Home > Vol 4, No 2 (2013) > ... dis-satisfaction as noted from this study should be addressed by the staff and management of the hospital.

  4. Setting wait times to achieve targeted left-without-being-seen rates.

    Science.gov (United States)

    Lucas, Jared; Batt, Robert J; Soremekun, Olanrewaju A

    2014-04-01

    Although several studies have demonstrated that wait time is a key factor that drives high leave-without-being-seen (LWBS) rates, limited data on ideal wait times and impact on LWBS rates exist. We studied the LWBS rates by triage class and target wait times required to achieve various LWBS rates. We conducted a 3-year retrospective analysis of patients presenting to an urban, tertiary, academic, adult emergency department (ED). We divided the 3-year study period into 504 discrete periods by year, day of the week, and hour of the day. Patients of same triage level arriving in the same bin were exposed to similar ED conditions. For each bin, we calculate the mean actual wait time and the proportion of patients that abandoned. We performed a regression analysis on the abandonment proportion on the mean wait time using weighted least squares regression. A total of 143,698 patients were included for analysis during the study period. The R(2) value was highest for Emergency Severity Index (ESI) 3 (R(2) = 0.88), suggesting that wait time is the major factor driving LWBS of ESI 3 patients. Assuming that ESI 2 patients wait less than 10 minutes, our sensitivity analysis shows that the target wait times for ESI 3 and ESI 4/5 patients should be less than 45 and 60 minutes, respectively, to achieve an overall LWBS rate of less than 2%. Achieving target LWBS rates requires analysis to understand the abandonment behavior and redesigning operations to achieve the target wait times. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Worth the Wait? Using Past Patterns to Determine Wait Periods for E-Books Released after Print

    Science.gov (United States)

    Kohn, Karen

    2018-01-01

    This paper asks if there is an optimal wait period for e-books that balances libraries' desire to acquire books soon after their publication with the frequent desire to purchase books electronically whenever feasible. Analyzing 13,043 titles that Temple University Libraries received on its e-preferred approval plan in 2014-15, the author looks at…

  6. Heart Surgery Waiting Time: Assessing the Effectiveness of an Action

    OpenAIRE

    Badakhshan, Abbas; Arab, Mohammad; Gholipour, Mahin; Behnampour, Naser; Saleki, Saeid

    2015-01-01

    Background: Waiting time is an index assessing patient satisfaction, managerial effectiveness and horizontal equity in providing health care. Although heart surgery centers establishment is attractive for politicians. They are always faced with the question of to what extent they solve patient’s problems. Objectives: The objective of this study was to evaluate factors influencing waiting time in patients of heart surgery centers, and to make recommendations for health-care policy-makers for r...

  7. The effects of immigration on NHS waiting times.

    Science.gov (United States)

    Giuntella, Osea; Nicodemo, Catia; Vargas-Silva, Carlos

    2018-03-01

    This paper analyzes the effects of immigration on waiting times for the National Health Service (NHS) in England. Linking administrative records from Hospital Episode Statistics (2003-2012) with immigration data drawn from the UK Labour Force Survey, we find that immigration reduced waiting times for outpatient referrals and did not have significant effects on waiting times in accident and emergency departments (A&E) and elective care. The reduction in outpatient waiting times can be explained by the fact that immigration increases natives' internal mobility and that immigrants tend to be healthier than natives who move to different areas. Finally, we find evidence that immigration increased waiting times for outpatient referrals in more deprived areas outside of London. The increase in average waiting times in more deprived areas is concentrated in the years immediately following the 2004 EU enlargement and disappears in the medium term (e.g., 3-4 years). Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  8. Longer wait times affect future use of VHA primary care.

    Science.gov (United States)

    Wong, Edwin S; Liu, Chuan-Fen; Hernandez, Susan E; Augustine, Matthew R; Nelson, Karin; Fihn, Stephan D; Hebert, Paul L

    2017-07-29

    Improving access to the Veterans Health Administration (VHA) is a high priority, particularly given statutory mandates of the Veterans Access, Choice and Accountability Act. This study examined whether patient-reported wait times for VHA appointments were associated with future reliance on VHA primary care services. This observational study examined 13,595 VHA patients dually enrolled in fee-for-service Medicare. Data sources included VHA administrative data, Medicare claims and the Survey of Healthcare Experiences of Patients (SHEP). Primary care use was defined as the number of face-to-face visits from VHA and Medicare in the 12 months following SHEP completion. VHA reliance was defined as the number of VHA visits divided by total visits (VHA+Medicare). Wait times were derived from SHEP responses measuring the usual number of days to a VHA appointment with patients' primary care provider for those seeking immediate care. We defined appointment wait times categorically: 0 days, 1day, 2-3 days, 4-7 days and >7 days. We used fractional logistic regression to examine the relationship between wait times and reliance. Mean VHA reliance was 88.1% (95% CI = 86.7% to 89.5%) for patients reporting 0day waits. Compared with these patients, reliance over the subsequent year was 1.4 (p = 0.041), 2.8 (p = 0.001) and 1.6 (p = 0.014) percentage points lower for patients waiting 2-3 days, 4-7 days and >7 days, respectively. Patients reporting longer usual wait times for immediate VHA care exhibited lower future reliance on VHA primary care. Longer wait times may reduce care continuity and impact cost shifting across two federal health programs. Copyright © 2017. Published by Elsevier Inc.

  9. Sci-Fri AM: Quality, Safety, and Professional Issues 04: Predicting waiting times in Radiation Oncology using machine learning

    International Nuclear Information System (INIS)

    Joseph, Ackeem; Herrera, David; Hijal, Tarek; Hendren, Laurie; Leung, Alvin; Wainberg, Justin; Sawaf, Marya; Maxim, Gorshkov; Maglieri, Robert; Keshavarz, Mehryar; Kildea, John

    2016-01-01

    We describe a method for predicting waiting times in radiation oncology. Machine learning is a powerful predictive modelling tool that benefits from large, potentially complex, datasets. The essence of machine learning is to predict future outcomes by learning from previous experience. The patient waiting experience remains one of the most vexing challenges facing healthcare. Waiting time uncertainty can cause patients, who are already sick and in pain, to worry about when they will receive the care they need. In radiation oncology, patients typically experience three types of waiting: Waiting at home for their treatment plan to be prepared Waiting in the waiting room for daily radiotherapy Waiting in the waiting room to see a physician in consultation or follow-up These waiting periods are difficult for staff to predict and only rough estimates are typically provided, based on personal experience. In the present era of electronic health records, waiting times need not be so uncertain. At our centre, we have incorporated the electronic treatment records of all previously-treated patients into our machine learning model. We found that the Random Forest Regression model provides the best predictions for daily radiotherapy treatment waiting times (type 2). Using this model, we achieved a median residual (actual minus predicted value) of 0.25 minutes and a standard deviation residual of 6.5 minutes. The main features that generated the best fit model (from most to least significant) are: Allocated time, median past duration, fraction number and the number of treatment fields.

  10. Sci-Fri AM: Quality, Safety, and Professional Issues 04: Predicting waiting times in Radiation Oncology using machine learning

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, Ackeem; Herrera, David; Hijal, Tarek; Hendren, Laurie; Leung, Alvin; Wainberg, Justin; Sawaf, Marya; Maxim, Gorshkov; Maglieri, Robert; Keshavarz, Mehryar; Kildea, John [McGill University Health Centre (Canada)

    2016-08-15

    We describe a method for predicting waiting times in radiation oncology. Machine learning is a powerful predictive modelling tool that benefits from large, potentially complex, datasets. The essence of machine learning is to predict future outcomes by learning from previous experience. The patient waiting experience remains one of the most vexing challenges facing healthcare. Waiting time uncertainty can cause patients, who are already sick and in pain, to worry about when they will receive the care they need. In radiation oncology, patients typically experience three types of waiting: Waiting at home for their treatment plan to be prepared Waiting in the waiting room for daily radiotherapy Waiting in the waiting room to see a physician in consultation or follow-up These waiting periods are difficult for staff to predict and only rough estimates are typically provided, based on personal experience. In the present era of electronic health records, waiting times need not be so uncertain. At our centre, we have incorporated the electronic treatment records of all previously-treated patients into our machine learning model. We found that the Random Forest Regression model provides the best predictions for daily radiotherapy treatment waiting times (type 2). Using this model, we achieved a median residual (actual minus predicted value) of 0.25 minutes and a standard deviation residual of 6.5 minutes. The main features that generated the best fit model (from most to least significant) are: Allocated time, median past duration, fraction number and the number of treatment fields.

  11. Analysing passenger arrivals rates and waiting time at bus stops

    OpenAIRE

    Kaparias, I.; Rossetti, C.; Trozzi, V.

    2015-01-01

    The present study investigates the rather under-explored topic of passenger waiting times at public transport facilities. Using data collected from part of London’s bus network by means of physical counts, measurements and observations, and complemented by on-site passenger interviews, the waiting behaviour is analysed for a number of bus stops served by different numbers of lines. The analysis employs a wide range of statistical methods and tools, and concentrates on three aspects: passenger...

  12. What Are We Waiting For Customer Wait Time, Fill Rate, And Marine Corps Equipment Operational Availability

    Science.gov (United States)

    2016-12-01

    directed the use of Customer Wait Time (CWT) as a measure of supply chain performance (Department of Defense [DOD], 2000). CWT is defined as “the total...time elapsed between issuance of a customer order and satisfaction of the order” (United States Marine Corps [USMC], 2014, pp. 2–29). In theory...rate is a widely used metric for setting inventory levels and is also a useful measure of customer satisfaction . In general, high fill-rates can be

  13. Heart Surgery Waiting Time: Assessing the Effectiveness of an Action.

    Science.gov (United States)

    Badakhshan, Abbas; Arab, Mohammad; Gholipour, Mahin; Behnampour, Naser; Saleki, Saeid

    2015-08-01

    Waiting time is an index assessing patient satisfaction, managerial effectiveness and horizontal equity in providing health care. Although heart surgery centers establishment is attractive for politicians. They are always faced with the question of to what extent they solve patient's problems. The objective of this study was to evaluate factors influencing waiting time in patients of heart surgery centers, and to make recommendations for health-care policy-makers for reducing waiting time and increasing the quality of services from this perspective. This cross-sectional study was performed in 2013. After searching articles on PubMed, Elsevier, Google Scholar, Ovid, Magiran, IranMedex, and SID, a list of several criteria, which relate to waiting time, was provided. Afterwards, the data on waiting time were collected by a researcher-structured checklist from 156 hospitalized patients. The data were analyzed by SPSS 16. The Kolmogorov Smirnov and Shapiro tests were used for determination of normality. Due to the non-normal distribution, non-parametric tests, such as Kruskal-Wallis and Mann-Whitney were chosen for reporting significance. Parametric tests also used reporting medians. Among the studied variables, just economic status had a significant relation with waiting time (P = 0.37). Fifty percent of participants had diabetes, whereas this estimate was 43.58% for high blood pressure. As the cause of delay, 28.2% of patients reported financial problems, 18.6% personal problem and 13.5% a delay in providing equipment by the hospital. It seems the studied hospital should review its waiting time arrangements and detach them, as far as possible, from subjective and personal (specialists) decisions. On the other hand, ministries of health and insurance companies should consider more financial support. It is also recommend that hospitals should arrange preoperational psychiatric consultation for increasing patients' emotionally readiness.

  14. The waiting time distribution as a graphical approach to epidemiologic measures of drug utilization

    DEFF Research Database (Denmark)

    Hallas, J; Gaist, D; Bjerrum, L

    1997-01-01

    that effectively conveys some essential utilization parameters for a drug. The waiting time distribution for a group of drug users is a charting of their first prescription presentations within a specified time window. For a drug used for chronic treatment, most current users will be captured at the beginning...... of the window. After a few months, the graph will be dominated by new, incident users. As examples, we present waiting time distributions for insulin, ulcer drugs, systemic corticosteroids, antidepressants, and disulfiram. Appropriately analyzed and interpreted, the waiting time distributions can provide...... information about the period prevalence, point prevalence, incidence, duration of use, seasonality, and rate of prescription renewal or relapse for specific drugs. Each of these parameters has a visual correlate. The waiting time distributions may be an informative supplement to conventional drug utilization...

  15. Improving Wait Times to Care for Individuals with Multimorbidities and Complex Conditions Using Value Stream Mapping

    Directory of Open Access Journals (Sweden)

    Tara Sampalli

    2015-07-01

    Full Text Available Background Recognizing the significant impact of wait times for care for individuals with complex chronic conditions, we applied a LEAN methodology, namely – an adaptation of Value Stream Mapping (VSM to meet the needs of people with multiple chronic conditions and to improve wait times without additional resources or funding. Methods Over an 18-month time period, staff applied a patient-centric approach that included LEAN methodology of VSM to improve wait times to care. Our framework of evaluation was grounded in the needs and perspectives of patients and individuals waiting to receive care. Patient centric views were obtained through surveys such as Patient Assessment of Chronic Illness Care (PACIC and process engineering based questions. In addition, LEAN methodology, VSM was added to identify non-value added processes contributing to wait times. Results The care team successfully reduced wait times to 2 months in 2014 with no wait times for care anticipated in 2015. Increased patient engagement and satisfaction are also outcomes of this innovative initiative. In addition, successful transformations and implementation have resulted in resource efficiencies without increase in costs. Patients have shown significant improvements in functional health following Integrated Chronic Care Service (ICCS intervention. The methodology will be applied to other chronic disease management areas in Capital Health and the province. Conclusion Wait times to care in the management of multimoribidities and other complex conditions can add a significant burden not only on the affected individuals but also on the healthcare system. In this study, a novel and modified LEAN methodology has been applied to embed the voice of the patient in care delivery processes and to reduce wait times to care in the management of complex chronic conditions.

  16. Evaluation of two dairy herd reproductive performance indicators that are adjusted for voluntary waiting period

    Directory of Open Access Journals (Sweden)

    Löf Emma

    2012-01-01

    Full Text Available Abstract Background Overall reproductive performance of dairy herds is monitored by various indicators. Most of them do not consider all eligible animals and do not consider different management strategies at farm level. This problem can be alleviated by measuring the proportion of pregnant cows by specific intervals after their calving date or after a fixed time period, such as the voluntary waiting period. The aim of this study was to evaluate two reproductive performance indicators that consider the voluntary waiting period at the herd. The two indicators were: percentage of pregnant cows in the herd after the voluntary waiting period plus 30 days (PV30 and percentage of inseminated cows in the herd after the voluntary waiting period plus 30 days (IV30. We wanted to assess how PV30 and IV30 perform in a simulation of herds with different reproductive management and physiology and to compare them to indicators of reproductive performance that do not consider the herd voluntary waiting period. Methods To evaluate the reproductive indicators we used the SimHerd-program, a stochastic simulation model, and 18 scenarios were simulated. The scenarios were designed by altering the reproductive management efficiency and the status of reproductive physiology of the herd. Logistic regression models, together with receiver operating characteristics (ROC, were used to examine how well the reproductive performance indicators could discriminate between herds of different levels of reproductive management efficiency or reproductive physiology. Results The logistic regression models with the ROC analysis showed that IV30 was the indicator that best discriminated between different levels of management efficiency followed by PV30, calving interval, 200-days not-in calf-rate (NotIC200, in calf rate at100-days (IC100 and a fertility index. For reproductive physiology the ROC analysis showed that the fertility index was the indicator that best discriminated

  17. Indication criteria for cataract extraction and gender differences in waiting time.

    Science.gov (United States)

    Smirthwaite, Goldina; Lundström, Mats; Albrecht, Susanne; Swahnberg, Katarina

    2014-08-01

    The purpose of this study was to investigate national indication criteria tool for cataract extraction (NIKE), a clinical tool for establishing levels of indications for cataract surgery, in relation to gender differences in waiting times for cataract extraction (CE). Data were collected by The Swedish National Cataract Register (NCR). Eye clinics report to NCR voluntarily and on regular basis (98% coverage). Comparisons regarding gender difference in waiting times were performed between NIKE-categorized and non-NIKE-categorized patients, as well as between different indication groups within the NIKE-system. All calculations were performed in spss version 20. Multivariate analyses were carried out using logistic regression, and single variable analyses were carried out by Student's t-test or chi square as appropriate. Gender, age, visual acuity and NIKE-categorization were associated with waiting time. Female patients had a longer waiting time to CE than male, both within and outside the NIKE-system. Gender difference in waiting time was somewhat larger among patients who had not been categorized by NIKE. In the non-NIKE-categorized group, women waited 0.20 months longer than men. In the group which was NIKE-categorized, women waited 0.18 months longer than men. It is reasonable to assume that prioritizing patients by means of NIKE helps to reduce the gender differences in waiting time. Gender differences in waiting time have decreased as NIKE was introduced and there may be a variety of explanations for this. However, with the chosen study design, we could not distinguish between effects related to NIKE and those due to other factors which occurred during the study period. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  18. Waiting Time Dynamics in Two-Dimensional Infrared Spectroscopy

    NARCIS (Netherlands)

    Jansen, Thomas L. C.; Knoester, Jasper

    We review recent work on the waiting time dynamics of coherent two-dimensional infrared (2DIR) spectroscopy. This dynamics can reveal chemical and physical processes that take place on the femto- and picosecond time scale, which is faster than the time scale that may be probed by, for example,

  19. Waiting time for cataract surgery and its influence on patient attitudes.

    Science.gov (United States)

    Chan, Frank Wan-kin; Fan, Alex Hoi; Wong, Fiona Yan-yan; Lam, Philip Tsze-ho; Yeoh, Eng-kiong; Yam, Carrie Ho-kwan; Griffiths, Sian; Lam, Dennis Shun-chiu; Congdon, Nathan

    2009-08-01

    To characterize willingness to pay for private operations and preferred waiting time among patients awaiting cataract surgery in Hong Kong. This was a cross-sectional survey. Subjects randomly selected from cataract surgical waiting lists in Hong Kong (n = 467) underwent a telephone interview based on a structured, validated questionnaire. Data were collected on private insurance coverage, preferred waiting time, amount willing to pay for surgery, and self-reported visual function and health status. Among 300 subjects completing the interview, 144 (48.2%) were 76 years of age or older, 177 (59%) were women, and mean time waiting for surgery was 17 +/- 15 months. Among 220 subjects (73.3%) willing to pay anything for surgery, the mean amount was US$552 +/- 443. With adjustment for age, education, and monthly household income, subjects willing to pay anything were less willing to wait 12 months for surgery (OR = 4.34; P = 0.002), more likely to know someone having had cataract surgery (OR = 2.20; P = 0.03), and more likely to use their own savings to pay for the surgery (OR = 2.21; P = 0.04). Subjects considering private cataract surgery, knowing people who have had cataract surgery, using nongovernment sources to pay for surgery, and having lower visual function were willing to pay more. Many patients wait significant periods for cataract surgery in Hong Kong, and are willing to pay substantial amounts for private operations. These results may have implications for other countries with cataract waiting lists.

  20. Waiting time and the psychosocial consequences of false-positive mammography

    DEFF Research Database (Denmark)

    Heleno, Bruno M.; Siersma, Volkert; Brodersen, John

    2015-01-01

    Background: There is wide variation in the psychosocial response to false-positive mammography. We aimed to assess whether women having to wait longer to exclude cancer had increased psychosocial consequences that persisted after cancer was ruled out. Findings: We selected women with false......-positive mammography (n = 272), screened for breast cancer in Copenhagen and Funen (Denmark) over a 1-year period. We measured psychosocial consequences immediately before women attended their recall visit and 1, 6, 18 and 36 months after women received their final diagnosis. After women were told that cancer had been...... ruled out, adverse psychosocial consequences decreased with time. We found no statistically significant differences between women who had cancer ruled out immediately at the recall visit (waiting time of 0) and women who had to wait longer before cancer was ruled out (waiting times 1-30, 30...

  1. Quality Improvement Cycles that Reduced Waiting Times at ...

    African Journals Online (AJOL)

    It was decided to undertake quality improvement (QI) cycles to analyse and improve the situation, using waiting time as a measure of improvement. Methods: A QI team was chosen to conduct two QI cycles. The allocated time for QI cycle 1 was from May to August 2006 and for QI cycle 2 from September to December 2006.

  2. Waiting Time Policies in the Health Care Sector. What Works?

    DEFF Research Database (Denmark)

    Christiansen, Terkel; Bech, Mickael

    2013-01-01

    times. In addition, a range of other measures may indirectly have affected waiting times, such as a general increase in spending on health care, the general practitioners’ role as gate-keepers, increased use of activity-based hospital reimbursement, increasing use of private heath insurance and private...

  3. Socioeconomic differences in waiting times for elective surgery: a population-based retrospective study

    Directory of Open Access Journals (Sweden)

    Petrelli Alessio

    2012-08-01

    Full Text Available Abstract Background Widespread literature on inequity in healthcare access and utilization has been published, but research on socioeconomic differences in waiting times is sparse and the evidence is fragmentary and controversial. The objective of the present study is the analysis of the relationship between individual socioeconomic level and waiting times for in-hospital elective surgery. Methods We retrospectively studied the waiting times experienced by patients registered on hospital waiting lists for 6 important surgical procedures by using the Hospital Discharge Database (HDD of the Piedmont Region (4,000,000 inhabitants in the North West of Italy from 2006 to 2008. The surgical procedures analyzed were: coronary artery by-pass (CABG, angioplasty, coronarography, endarterectomy, hip replacement and cholecystectomy. Cox regression models were estimated to study the relationship between waiting times and educational level taking into account the confounding effect of the following factors: sex, age, comorbidity, registration period, and Local Health Authorities (LHA as a proxy of supply. Results Median waiting times for low educational level were higher than for high educational level for all the selected procedures. Differences were particularly high for endarterectomy and hip replacement. For all considered procedures, except CABG, an inverse gradient between waiting times and educational level was observed: the conditional probabilities of undergoing surgery were lower among individuals with a low to middle level education than for individuals with a higher level of education after adjustment for sex, age, comorbidities, registration period, and LHAs. For most procedures the effect decreases over the follow up period. Conclusions The results of the study show evidence of inequalities in access to elective surgery in Italy. Implementation of policies aimed to promote national information initiatives that guarantee wider access to those

  4. EVALUTION OF THE SINGLE INTERCITY FREIGHT TRANSPORTATION WAITING TIME

    Directory of Open Access Journals (Sweden)

    N. Ponomariova

    2015-07-01

    Full Text Available The example of vechicle operation on the pendulum intercity route during single freightages processing is considered. Two approaches to the definition of the single freightage waiting time by the carrier are proposed. These approaches allow to take into account the probability of the single freightage obtaining by the carrier during the different load level of the transport enterprise capacity.

  5. Potential impact of enhanced practice efficiency on endoscopy waiting times.

    LENUS (Irish Health Repository)

    Harewood, G C

    2009-06-01

    With the growing demand on endoscopy services, optimising practice efficiency has assumed increasing importance. Prior research has identified practice changes, which increase the efficiency in endoscopy. In this study, the potential impact of these practice changes on the current and projected future endoscopy waiting times at our institution was assessed.

  6. Waiting Time Increases Risk of Attrition in Gambling Disorder Treatment

    DEFF Research Database (Denmark)

    Linnet, Jakob; Pedersen, Anders Sune

    2014-01-01

    Attrition is a well known problem in psychotherapeutic treatment. Patients with addiction have high attrition rates, and it is therefore important to identify factors that can improve completion rates in addiction. Here, we investigated the influence of waiting time as a predictor of treatment...

  7. Incorporating waiting time in competitive location models: Formulations and heuristics

    OpenAIRE

    Silva, Francisco; Serra, Daniel

    2008-01-01

    In this paper we propose a metaheuristic to solve a new version of the Maximum Capture Problem. In the original MCP, market capture is obtained by lower traveling distances or lower traveling time, in this new version not only the traveling time but also the waiting time will affect the market share. This problem is hard to solve using standard optimization techniques. Metaheuristics are shown to offer accurate results within acceptable computing times.

  8. Patient Satisfaction Is Associated With Time With Provider But Not Clinic Wait Time Among Orthopedic Patients.

    Science.gov (United States)

    Patterson, Brendan M; Eskildsen, Scott M; Clement, R Carter; Lin, Feng-Chang; Olcott, Christopher W; Del Gaizo, Daniel J; Tennant, Joshua N

    2017-01-01

    Clinic wait time is considered an important predictor of patient satisfaction. The goal of this study was to determine whether patient satisfaction among orthopedic patients is associated with clinic wait time and time with the provider. The authors prospectively enrolled 182 patients at their outpatient orthopedic clinic. Clinic wait time was defined as the time between patient check-in and being seen by the surgeon. Time spent with the provider was defined as the total time the patient spent in the examination room with the surgeon. The Consumer Assessment of Healthcare Providers and Systems survey was used to measure patient satisfaction. Factors associated with increased patient satisfaction included patient age and increased time with the surgeon (P=.024 and P=.037, respectively), but not clinic wait time (P=.625). Perceived wait time was subject to a high level of error, and most patients did not accurately report whether they had been waiting longer than 15 minutes to see a provider until they had waited at least 60 minutes (P=.007). If the results of the current study are generalizable, time with the surgeon is associated with patient satisfaction in orthopedic clinics, but wait time is not. Further, the study findings showed that patients in this setting did not have an accurate perception of actual wait time, with many patients underestimating the time they waited to see a provider. Thus, a potential strategy for improving patient satisfaction is to spend more time with each patient, even at the expense of increased wait time. [Orthopedics. 2017; 40(1):43-48.]. Copyright 2016, SLACK Incorporated.

  9. Wait times in the emergency department for patients with mental illness

    Science.gov (United States)

    Atzema, Clare L.; Schull, Michael J.; Kurdyak, Paul; Menezes, Natasja M.; Wilton, Andrew S.; Vermuelen, Marian J.; Austin, Peter C.

    2012-01-01

    Background: It has been suggested that patients with mental illness wait longer for care than other patients in the emergency department. We determined wait times for patients with and without mental health diagnoses during crowded and noncrowded periods in the emergency department. Methods: We conducted a population-based retrospective cohort analysis of adults seen in 155 emergency departments in Ontario between April 2007 and March 2009. We compared wait times and triage scores for patients with mental illness to those for all other patients who presented to the emergency department during the study period. Results: The patients with mental illness (n = 51 381) received higher priority triage scores than other patients, regardless of crowding. The time to assessment by a physician was longer overall for patients with mental illness than for other patients (median 82, interquartile range [IQR] 41–147 min v. median 75 [IQR 36–140] min; p < 0.001). The median time from the decision to admit the patient to hospital to ward transfer was markedly shorter for patients with mental illness than for other patients (median 74 [IQR 15–215] min v. median 152 [IQR 45–605] min; p < 0.001). After adjustment for other variables, patients with mental illness waited 10 minutes longer to see a physician compared with other patients during noncrowded periods (95% confidence interval [CI] 8 to 11), but they waited significantly less time than other patients as crowding increased (mild crowding: −14 [95% CI −12 to −15] min; moderate crowding: −38 [95% CI −35 to −42] min; severe crowding: −48 [95% CI −39 to −56] min; p < 0.001). Interpretation: Patients with mental illness were triaged appropriately in Ontario’s emergency departments. These patients waited less time than other patients to see a physician under crowded conditions and only slightly longer under noncrowded conditions. PMID:23148052

  10. The 2012 SAGE wait times program: Survey of Access to GastroEnterology in Canada

    Science.gov (United States)

    Leddin, Desmond; Armstrong, David; Borgaonkar, Mark; Bridges, Ronald J; Fallone, Carlo A; Telford, Jennifer J; Chen, Ying; Colacino, Palma; Sinclair, Paul

    2013-01-01

    BACKGROUND: Periodically surveying wait times for specialist health services in Canada captures current data and enables comparisons with previous surveys to identify changes over time. METHODS: During one week in April 2012, Canadian gastroenterologists were asked to complete a questionnaire (online or by fax) recording demographics, reason for referral, and dates of referral and specialist visits for at least 10 consecutive new patients (five consultations and five procedures) who had not been seen previously for the same indication. Wait times were determined for 18 indications and compared with those from similar surveys conducted in 2008 and 2005. RESULTS: Data regarding adult patients were provided by 173 gastroenterologists for 1374 consultations, 540 procedures and 293 same-day consultations and procedures. Nationally, the median wait times were 92 days (95% CI 85 days to 100 days) from referral to consultation, 55 days (95% CI 50 days to 61 days) from consultation to procedure and 155 days (95% CI 142 days to 175 days) (total) from referral to procedure. Overall, wait times were longer in 2012 than in 2005 (Pgastroenterology services continue to exceed recommended targets, remain unchanged since 2008 and exceed wait times reported in 2005. PMID:23472243

  11. Reducing wait time in a hospital pharmacy to promote customer service.

    Science.gov (United States)

    Slowiak, Julie M; Huitema, Bradley E; Dickinson, Alyce M

    2008-01-01

    The purpose of this study was to compare the effects of 2 different interventions on wait times at a hospital outpatient pharmacy: (1) giving feedback to employees about customer satisfaction with wait times and (2) giving a combined intervention package that included giving more specific feedback about actual wait times and goal setting for wait time reduction in addition to the customer satisfaction feedback. The relationship between customer satisfaction ratings and wait times was examined to determine whether wait times affected customer service satisfaction. Participants were 10 employees (4 pharmacists and 6 technicians) of an outpatient pharmacy. Wait times and customer satisfaction ratings were collected for "waiting customers." An ABCBA' within-subjects design was used to assess the effects of the interventions on both wait time and customer satisfaction, where A was the baseline (no feedback and no goal setting); B was the customer satisfaction feedback; C was the customer satisfaction feedback, the wait time feedback, and the goal setting for wait time reduction; and A' was a follow-up condition that was similar to the original baseline condition. Wait times were reduced by approximately 20%, and there was concomitant increased shift in levels of customer satisfaction, as indicated by the correlation between these variables (r = -0.57 and P customer's wait time. Data from this study may provide useful preliminary benchmarking data for standard pharmacy wait times.

  12. Renewal processes based on generalized Mittag-Leffler waiting times

    Science.gov (United States)

    Cahoy, Dexter O.; Polito, Federico

    2013-03-01

    The fractional Poisson process has recently attracted experts from several fields of study. Its natural generalization of the ordinary Poisson process made the model more appealing for real-world applications. In this paper, we generalized the standard and fractional Poisson processes through the waiting time distribution, and showed their relations to an integral operator with a generalized Mittag-Leffler function in the kernel. The waiting times of the proposed renewal processes have the generalized Mittag-Leffler and stretched-squashed Mittag-Leffler distributions. Note that the generalizations naturally provide greater flexibility in modeling real-life renewal processes. Algorithms to simulate sample paths and to estimate the model parameters are derived. Note also that these procedures are necessary to make these models more usable in practice. State probabilities and other qualitative or quantitative features of the models are also discussed.

  13. An Elementary Derivation of Mean Wait Time in Polling Systems

    OpenAIRE

    Cady, Field

    2012-01-01

    Polling systems are a well-established subject in queueing theory. However, their formal treatments generally rely heavily on relatively sophisticated theoretical tools, such as moment generating functions and Laplace transforms, and solutions often require the solution of large systems of equations. We show that, if you are willing to only have the average waiting of a system time rather than higher moments, it can found through an elementary derivation based only on algebra and some well-kn...

  14. 78 FR 68705 - Premerger Notification; Reporting and Waiting Period Requirements

    Science.gov (United States)

    2013-11-15

    ... the legislative history of the HSR Act suggest that the Commission may not use its broad rulemaking... information in a timely and useful fashion.\\35\\ \\34\\ 44 U.S.C. 3508: Determination of necessity for...

  15. Spatial structure increases the waiting time for cancer

    Science.gov (United States)

    Martens, Erik A.; Kostadinov, Rumen; Maley, Carlo C.; Hallatschek, Oskar

    2011-11-01

    Cancer results from a sequence of genetic and epigenetic changes that lead to a variety of abnormal phenotypes including increased proliferation and survival of somatic cells and thus to a selective advantage of pre-cancerous cells. The notion of cancer progression as an evolutionary process has been attracting increasing interest in recent years. A great deal of effort has been made to better understand and predict the progression to cancer using mathematical models; these mostly consider the evolution of a well-mixed cell population, even though pre-cancerous cells often evolve in highly structured epithelial tissues. In this study, we propose a novel model of cancer progression that considers a spatially structured cell population where clones expand via adaptive waves. This model is used to assess two different paradigms of asexual evolution that have been suggested to delineate the process of cancer progression. The standard scenario of periodic selection assumes that driver mutations are accumulated strictly sequentially over time. However, when the mutation supply is sufficiently high, clones may arise simultaneously on distinct genetic backgrounds, and clonal adaptation waves interfere with each other. We find that in the presence of clonal interference, spatial structure increases the waiting time for cancer, leads to a patchwork structure of non-uniformly sized clones and decreases the survival probability of virtually neutral (passenger) mutations, and that genetic distance begins to increase over a characteristic length scale Lc. These characteristic features of clonal interference may help us to predict the onset of cancers with pronounced spatial structure and to interpret spatially sampled genetic data obtained from biopsies. Our estimates suggest that clonal interference likely occurs in the progression of colon cancer and possibly other cancers where spatial structure matters.

  16. Computation and evaluation of scheduled waiting time for railway networks

    DEFF Research Database (Denmark)

    Landex, Alex

    2010-01-01

    Timetables are affected by scheduled waiting time (SWT) that prolongs the travel times for trains and thereby passengers. SWT occurs when a train hinders another train to run with the wanted speed. The SWT affects both the trains and the passengers in the trains. The passengers may be further...... affected due to longer transfer times to other trains. SWT can be estimated analytically for a given timetable or by simulation of timetables and/or plans of operation. The simulation of SWT has the benefit that it is possible to examine the entire network. This makes it possible to improve the future...

  17. Time on wait lists for coronary bypass surgery in British Columbia, Canada, 1991 – 2000

    Directory of Open Access Journals (Sweden)

    Hayden Robert

    2005-03-01

    Full Text Available Abstract Background In British Columbia, Canada, all necessary medical services are funded publicly. Concerned with growing wait lists in the mid-1990s, the provincial government started providing extra funding for coronary artery bypass grafting (CABG operations annually. Although aimed at improving access, it is not known whether supplementary funding changed the time that patients spent on wait lists for CABG. We sought to determine whether the period of registration on wait lists had an effect on time to isolated CABG and whether the period effect was similar across priority groups. Methods Using records from a population-based registry, we studied the wait-list time before and after supplementary funding became available. We compared the number of weeks from registration to surgery for equal proportions of patients in synthetic cohorts defined by five registration periods in the 1990s. Results Overall, 9,231 patients spent a total of 137,126 person-weeks on the wait lists. The time to surgery increased by the middle of the decade, and decreased toward the end of the decade. Relative to the 1991–92 registration period, the conditional weekly probabilities of undergoing surgery were 30% lower among patients registered on the wait lists in 1995–96, hazard ratio (HR = 0.70 (0.65–0.76, and 23% lower in 1997–98 patients, HR = 0.77 (0.71–0.83, while there were no differences with 1999–2000 patients, HR = 0.94 (0.88–1.02, after adjusting for priority group at registration, comorbidity, age and sex. We found that the effect of registration period was different across priority groups. Conclusion Our results provide evidence that time to CABG shortened after supplementary funding was provided on an annual basis to tertiary care hospitals within a single publicly funded health system. One plausible explanation is that these hospitals had capacity to increase the number of operations. At the same time, the effect was not uniform across

  18. Canadian Consensus on Medically Acceptable Wait Times for Digestive Health Care

    Directory of Open Access Journals (Sweden)

    William G Paterson

    2006-01-01

    Full Text Available BACKGROUND: Delays in access to health care in Canada have been reported, but standardized systems to manage and monitor wait lists and wait times, and benchmarks for appropriate wait times, are lacking. The objective of the present consensus was to develop evidence- and expertise-based recommendations for medically appropriate maximal wait times for consultation and procedures by a digestive disease specialist.

  19. Pooled Open Blocks Shorten Wait Times for Nonelective Surgical Cases.

    Science.gov (United States)

    Zenteno, Ana C; Carnes, Tim; Levi, Retsef; Daily, Bethany J; Price, Devon; Moss, Susan C; Dunn, Peter F

    2015-07-01

    Assess the impact of the implementation of a data-driven scheduling strategy that aimed to improve the access to care of nonelective surgical patients at Massachusetts General Hospital (MGH). Between July 2009 and June 2010, MGH experienced increasing throughput challenges in its perioperative environment: approximately 30% of the nonelective patients were waiting more than the prescribed amount of time to get to surgery, hampering access to care and aggravating the lack of inpatient beds. This work describes the design and implementation of an "open block" strategy: operating room (OR) blocks were reserved for nonelective patients during regular working hours (prime time) and their management centralized. Discrete event simulation showed that 5 rooms would decrease the percentage of delayed patients from 30% to 2%, assuming that OR availability was the only reason for preoperative delay. Implementation began in January 2012. We compare metrics for June through December of 2012 against the same months of 2011. The average preoperative wait time of all nonelective surgical patients decreased by 25.5% (P reason for delay. Rigorous metrics were developed to evaluate its performance. Strong managerial leadership was crucial to enact the new practices and turn them into organizational change.

  20. Provisions on waiting periods in international investment protection treaties and their impact on the jurisdiction of arbitral tribunals

    Directory of Open Access Journals (Sweden)

    Đundić Petar

    2012-01-01

    Full Text Available Provisions on so-called waiting periods in international investment protection treaties give an investor from one contracting state an opportunity to initiate arbitration against the host state provided that the time designated by the treaty from the date on which the dispute arose has elapsed. The aim of those provisions is to enable parties to the dispute to use this time for consultations and attempt to reach a negotiated settlement. The paper analyzes the attitude of contemporary arbitral practice towards the legal nature and effect of those provisions on tribunals' jurisdiction in investment disputes. The analysis shows gradual and clear shift of position taken by the tribunals in cases in which claimants did not comply with waiting periods. Because arbitral tribunals today are more resolved to penalize premature submission of the dispute to arbitration than they were one decade ago, in the future one can expect much more cautious conduct of potential claimants in this regard.

  1. Hospital Capacity, Waiting Times and Sick Leave Duration - an Empirical Analysis of a Norwegian Health Policy Reform

    OpenAIRE

    Aakvik, Arild; Holmås, Tor Helge; Kjerstad, Egil

    2012-01-01

    A health policy reform aiming to reduce hospital waiting times and sickness absences, the Faster Return to Work (FRW) scheme, is evaluated by creating treatment and control groups to facilitate causal interpretations of the empirical results. We use a unique dataset on individuals where we match hospital data with social security data and socio-economic characteristics. The main idea behind the reform is that long waiting times for hospital treatment lead to unnecessarily long periods of sick...

  2. Minimizing patient waiting time in emergency department of public hospital using simulation optimization approach

    Science.gov (United States)

    Ibrahim, Ireen Munira; Liong, Choong-Yeun; Bakar, Sakhinah Abu; Ahmad, Norazura; Najmuddin, Ahmad Farid

    2017-04-01

    Emergency department (ED) is the main unit of a hospital that provides emergency treatment. Operating 24 hours a day with limited number of resources invites more problems to the current chaotic situation in some hospitals in Malaysia. Delays in getting treatments that caused patients to wait for a long period of time are among the frequent complaints against government hospitals. Therefore, the ED management needs a model that can be used to examine and understand resource capacity which can assist the hospital managers to reduce patients waiting time. Simulation model was developed based on 24 hours data collection. The model developed using Arena simulation replicates the actual ED's operations of a public hospital in Selangor, Malaysia. The OptQuest optimization in Arena is used to find the possible combinations of a number of resources that can minimize patients waiting time while increasing the number of patients served. The simulation model was modified for improvement based on results from OptQuest. The improvement model significantly improves ED's efficiency with an average of 32% reduction in average patients waiting times and 25% increase in the total number of patients served.

  3. Determining prescription durations based on the parametric waiting time distribution

    DEFF Research Database (Denmark)

    Støvring, Henrik; Pottegård, Anton; Hallas, Jesper

    2016-01-01

    two-component mixture model for the waiting time distribution (WTD). The distribution component for prevalent users estimates the forward recurrence density (FRD), which is related to the distribution of time between subsequent prescription redemptions, the inter-arrival density (IAD), for users...... in continued treatment. We exploited this to estimate percentiles of the IAD by inversion of the estimated FRD and defined the duration of a prescription as the time within which 80% of current users will have presented themselves again. Statistical properties were examined in simulation studies......-Normal). When the IAD consisted of a mixture of two Log-Normal distributions, but was analyzed with a single Log-Normal distribution, relative bias did not exceed 9%. Using a Log-Normal FRD, we estimated prescription durations of 117, 91, 137, and 118 days for NSAIDs, warfarin, bendroflumethiazide...

  4. Reducing pharmacy wait time to promote customer service: a follow-up study.

    Science.gov (United States)

    Slowiak, Julie M; Huitema, Bradley E

    2015-01-01

    The present study had 3 objectives: (1) to evaluate the effects of 2 different interventions (feedback regarding customer satisfaction with wait time and combined feedback and goal setting) on wait time in a hospital outpatient pharmacy; (2) to assess the extent to which the previously applied interventions maintained their effects; and (3) to evaluate the differences between the effects of the original study and those of the present follow-up study. Participants were 10 employees (4 pharmacists and 6 technicians) of an outpatient pharmacy. Wait times and customer satisfaction ratings were collected for "waiting customers." An ABCB within-subjects design was used to assess the effects of the interventions on both wait time and customer satisfaction, where A was the baseline (no feedback and no goal setting); B was the customer satisfaction feedback; and C was the customer satisfaction feedback, the wait time feedback, and the goal setting for wait time reduction. Wait time decreased after baseline when the combined intervention was introduced, and wait time increased with the reintroduction of satisfaction feedback (alone). The results of the replication study confirm the pattern of the results of the original study and demonstrate high sensitivity of levels of customer satisfaction with wait time. The most impressive result of the replication is the nearly 2-year maintenance of lower wait time between the end of the original study and the beginning (baseline) of the replication.

  5. A model to prioritize access to elective surgery on the basis of clinical urgency and waiting time

    Directory of Open Access Journals (Sweden)

    Santori Gregorio

    2009-01-01

    test period, fully covering the case mix of the patients referred to surgery. The software produced real time data and advanced parameters, providing patients and users useful tools to manage waiting lists and to schedule hospital admissions with ease and efficiency. The model protected patients from horizontal and vertical inequities, while positive changes in API were observed in the latest period, meaning that more patients were treated within their MTBT. Conclusion The SWALIS model achieves the purpose of providing useful data to monitor waiting lists appropriately. It allows homogeneous and standardized prioritization, enhancing transparency, efficiency and equity. Due to its applicability, it might represent a pragmatic approach towards surgical waiting lists, useful in both clinical practice and strategic resource management.

  6. The British Columbia Nephrologists' Access Study (BCNAS) - a prospective, health services interventional study to develop waiting time benchmarks and reduce wait times for out-patient nephrology consultations.

    Science.gov (United States)

    Schachter, Michael E; Romann, Alexandra; Djurdev, Ognjenka; Levin, Adeera; Beaulieu, Monica

    2013-08-29

    Early referral and management of high-risk chronic kidney disease may prevent or delay the need for dialysis. Automatic eGFR reporting has increased demand for out-patient nephrology consultations and in some cases, prolonged queues. In Canada, a national task force suggested the development of waiting time targets, which has not been done for nephrology. We sought to describe waiting time for outpatient nephrology consultations in British Columbia (BC). Data collection occurred in 2 phases: 1) Baseline Description (Jan 18-28, 2010) and 2) Post Waiting Time Benchmark-Introduction (Jan 16-27, 2012). Waiting time was defined as the interval from receipt of referral letters to assessment. Using a modified Delphi process, Nephrologists and Family Physicians (FP) developed waiting time targets for commonly referred conditions through meetings and surveys. Rules were developed to weigh-in nephrologists', FPs', and patients' perspectives in order to generate waiting time benchmarks. Targets consider comorbidities, eGFR, BP and albuminuria. Referred conditions were assigned a priority score between 1-4. BC nephrologists were encouraged to centrally triage referrals to see the first available nephrologist. Waiting time benchmarks were simultaneously introduced to guide patient scheduling. A post-intervention waiting time evaluation was then repeated. In 2010 and 2012, 43/52 (83%) and 46/57 (81%) of BC nephrologists participated. Waiting time decreased from 98(IQR44,157) to 64(IQR21,120) days from 2010 to 2012 (p = management associated with improved access to nephrologists in BC. Improvements in waiting time was most marked for the highest priority patients, which suggests that benchmarks had an influence on triaging behavior. Further research is needed to determine whether this effect is sustainable.

  7. The importance of patient expectations as a determinant of satisfaction with waiting times for hip and knee replacement surgery.

    Science.gov (United States)

    Conner-Spady, Barbara L; Sanmartin, Claudia; Johnston, Geoffrey H; McGurran, John J; Kehler, Melissa; Noseworthy, Tom W

    2011-08-01

    The disconfirmation model hypothesizes that satisfaction is a function of a perceived discrepancy from an initial expectation. Our objectives were: (1) to test the disconfirmation model as it applies to patient satisfaction with waiting time (WT) and (2) to build an explanatory model of the determinants of satisfaction with WT for hip and knee replacement. We mailed 1000 questionnaires to 2 random samples: patients waiting or those who had received a joint replacement within the preceding 3-12 months. We used ordinal logistic regression analysis to build an explanatory model of the determinants of satisfaction. Of the 1330 returned surveys, 1240 contained patient satisfaction data. The sample was 57% female; mean age was 70 years (SD 11). Consistent with the disconfirmation model, when their WTs were longer than expected, both waiting (OR 5.77, 95% CI 3.57-9.32) and post-surgery patients (OR 6.57, 95% CI 4.21-10.26) had greater odds of dissatisfaction, adjusting for the other variables in the model. Compared to those who waited 3 months or less, post-surgery patients who waited 6 to 12 months (OR 2.59, 95% CI 1.27-5.27) and over 12 months (OR 3.30, 95% CI 1.65-6.58) had greater odds of being dissatisfied with their waiting time. Patients who felt they were treated unfairly had greater odds of being dissatisfied (OR 4.74, 95% CI 2.60-8.62). In patients on waiting lists and post-surgery for hip and knee replacement, satisfaction with waiting times is related to fulfillment of expectations about waiting, as well as a perception of fairness. Measures to modify expectations and increase perceived fairness, such as informing patients of a realistic WT and communication during the waiting period, may increase satisfaction with WTs. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  8. Success Run Waiting Times and Fuss-Catalan Numbers

    Directory of Open Access Journals (Sweden)

    S. J. Dilworth

    2015-01-01

    Full Text Available We present power series expressions for all the roots of the auxiliary equation of the recurrence relation for the distribution of the waiting time for the first run of k consecutive successes in a sequence of independent Bernoulli trials, that is, the geometric distribution of order k. We show that the series coefficients are Fuss-Catalan numbers and write the roots in terms of the generating function of the Fuss-Catalan numbers. Our main result is a new exact expression for the distribution, which is more concise than previously published formulas. Our work extends the analysis by Feller, who gave asymptotic results. We obtain quantitative improvements of the error estimates obtained by Feller.

  9. Waiting Time Distributions for Pattern Occurrence in a Constrained Sequence

    Directory of Open Access Journals (Sweden)

    Valeri Stefanov

    2007-01-01

    Full Text Available A binary sequence of zeros and ones is called a (d,k-sequence if it does not contain runs of zeros of length either less than d or greater than k, where d and k are arbitrary, but fixed, non-negative integers and d < k. Such sequences find an abundance of applications in communications, in particular for magnetic and optical recording. Occasionally, one requires that (d,k-sequences do not contain a specific pattern w. Therefore, distribution results concerning pattern occurrence in (d,k-sequences are of interest. In this paper we study the distribution of the waiting time until the r th occurrence of a pattern w in a random (d,k-sequence generated by a Markov source. Numerical examples are also provided.

  10. Associations Between Waiting Times, Service Times, and Patient Satisfaction in an Endocrinology Outpatient Department: A Time Study and Questionnaire Survey.

    Science.gov (United States)

    Xie, Zhenzhen; Or, Calvin

    2017-01-01

    The issue of long patient waits has attracted increasing public attention due to the negative effects of waiting on patients' satisfaction with health care. The present study examined the associations between actual waiting time, perceived acceptability of waiting time, actual service time, perceived acceptability of service time, actual visit duration, and the level of patient satisfaction with care. We conducted a cross-sectional time study and questionnaire survey of endocrinology outpatients visiting a major teaching hospital in China. Our results show that actual waiting time was negatively associated with patient satisfaction regarding several aspects of the care they received. Also, patients who were less satisfied with the sociocultural atmosphere and the identity-oriented approach to their care tended to perceive the amounts of time they spent waiting and receiving care as less acceptable. It is not always possible to prevent dissatisfaction with waiting, or to actually reduce waiting times by increasing resources such as increased staffing. However, several improvements in care services can be considered. Our suggestions include providing clearer, more transparent information to keep patients informed about the health care services that they may receive, and the health care professionals who are responsible for those services. We also suggest that care providers are encouraged to continue to show empathy and respect for patients, that patients are provided with private areas where they can talk with health professionals and no one can overhear, and that hospital staff treat the family members or friends who accompany patients in a courteous and friendly way.

  11. The effect of waiting times on demand and supply for elective surgery: Evidence from Italy.

    Science.gov (United States)

    Riganti, Andrea; Siciliani, Luigi; Fiorio, Carlo V

    2017-09-01

    Waiting times are a major policy concern in publicly funded health systems across OECD countries. Economists have argued that, in the presence of excess demand, waiting times act as nonmonetary prices to bring demand for and supply of health care in equilibrium. Using administrative data disaggregated by region and surgical procedure over 2010-2014 in Italy, we estimate demand and supply elasticities with respect to waiting times. We employ linear regression models with first differences and instrumental variables to deal with endogeneity of waiting times. We find that demand is inelastic to waiting times while supply is more elastic. Estimates of demand elasticity are between -0.15 to -0.24. Our results have implications on the effectiveness of policies aimed at increasing supply and their ability to reduce waiting times. Copyright © 2017 John Wiley & Sons, Ltd.

  12. Waiting time disparities in breast cancer diagnosis and treatment: a population-based study in France.

    Science.gov (United States)

    Molinié, F; Leux, C; Delafosse, P; Ayrault-Piault, S; Arveux, P; Woronoff, A S; Guizard, A V; Velten, M; Ganry, O; Bara, S; Daubisse-Marliac, L; Tretarre, B

    2013-10-01

    Waiting times are key indicators of a health's system performance, but are not routinely available in France. We studied waiting times for diagnosis and treatment according to patients' characteristics, tumours' characteristics and medical management options in a sample of 1494 breast cancers recorded in population-based registries. The median waiting time from the first imaging detection to the treatment initiation was 34 days. Older age, co-morbidity, smaller size of tumour, detection by organised screening, biopsy, increasing number of specimens removed, multidisciplinary consulting meetings and surgery as initial treatment were related to increased waiting times in multivariate models. Many of these factors were related to good practices guidelines. However, the strong influence of organised screening programme and the disparity of waiting times according to geographical areas were of concern. Better scheduling of diagnostic tests and treatment propositions should improve waiting times in the management of breast cancer in France. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Relative entropy and waiting time for continuous-time Markov processes

    NARCIS (Netherlands)

    Chazottes, J.R.; Giardinà, C.; Redig, F.H.J.

    2006-01-01

    For discrete-time stochastic processes, there is a close connection between return (resp. waiting) times and entropy (resp. relative entropy). Such a connection cannot be straightforwardly extended to the continuous-time setting. Contrarily to the discrete-time case one needs a reference measure on

  14. Effect of self-triage on waiting times at a walk-in sexual health clinic.

    Science.gov (United States)

    Hitchings, Samantha; Barter, Janet

    2009-10-01

    Lengthy waiting times can be a major problem in walk-in sexual health clinics. They are stressful for both patients and staff and may lead to clients with significant health issues leaving the department before being seen by a clinician. A self-triage system may help reduce waiting times and duplication of work, improve patient pathways and decrease wasted visits. This paper describes implementation of a self-triage system in two busy sexual and reproductive health clinics. Patients were asked to complete a self-assessment form on registration to determine the reason for attendance. This then enabled patients to be directed to the most appropriate specialist or clinical service. The benefits of this approach were determined by measuring patient waiting times, reduction in unnecessary specialist review together with patient acceptability as tested by a patient satisfaction survey. The ease of comprehension of the triage form was also assessed by an independent readers' panel. A total of 193 patients were recruited over a 4-month period from November 2004 to February 2005. Patients from the November and December clinics were assigned to the 'traditional treatment' arm, with patients at subsequent clinics being assigned to the 'self-triage' system. Waiting times were collected by the receptionist and clinic staff. Ninety six patients followed the traditional route, 97 the new self-triage system. Sixty-nine (35.8%) patients completed the satisfaction survey. The self-triage system significantly reduced waiting time from 40 (22, 60) to 23 (10, 40) minutes [results expressed as median (interquartile range)]. There was a non-significant reduction in the proportion of patients seeing two clinicians from 21% to 13% (p = 0.17). Satisfaction levels were not significantly altered (95% compared to 97% satisfied, p = 0.64). The readers' panel found the triage form both easy to understand and to complete. Self-triage can effectively reduce clinic waiting times and allow better

  15. [Patients' satisfaction and waiting time in oncology day care centers in Champagne-Ardenne].

    Science.gov (United States)

    Debreuve-Theresette, A; Jovenin, N; Stona, A C; Kraïem-Leleu, M; Burde, F; Parent, D; Hettler, D; Rey, J B

    2015-12-01

    Quality of life of patients suffering from cancer may be influenced by the way healthcare is organized and by patient experiences. Nowadays, chemotherapy is often provided in day care centers. This study aimed to assess patient waiting time and satisfaction in oncology day care centers in Champagne-Ardenne, France. This cross-sectional survey involved all patients receiving ambulatory chemotherapy during a one-week period in day care centers of Champagne-Ardenne public and private healthcare institutions participating in the study. Sociodemographic, medical and outpatient data were collected. Patient satisfaction was measured using the Out-Patsat35 questionnaire. Eleven (out of 16) oncology day care centers and 441 patients participated in the study. Most of the patients were women (n=252, 57.1%) and the mean age was 61±12 years. The mean satisfaction score was 82±14 (out of 100) and the mean waiting time between the assigned appointment time and administration of chemotherapy was 97±60 min. This study has shown that waiting times are important. However, patients are satisfied with the healthcare organization, especially regarding nursing support. Early preparation of chemotherapy could improve these parameters. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  16. Models of emergency departments for reducing patient waiting times.

    Directory of Open Access Journals (Sweden)

    Marek Laskowski

    Full Text Available In this paper, we apply both agent-based models and queuing models to investigate patient access and patient flow through emergency departments. The objective of this work is to gain insights into the comparative contributions and limitations of these complementary techniques, in their ability to contribute empirical input into healthcare policy and practice guidelines. The models were developed independently, with a view to compare their suitability to emergency department simulation. The current models implement relatively simple general scenarios, and rely on a combination of simulated and real data to simulate patient flow in a single emergency department or in multiple interacting emergency departments. In addition, several concepts from telecommunications engineering are translated into this modeling context. The framework of multiple-priority queue systems and the genetic programming paradigm of evolutionary machine learning are applied as a means of forecasting patient wait times and as a means of evolving healthcare policy, respectively. The models' utility lies in their ability to provide qualitative insights into the relative sensitivities and impacts of model input parameters, to illuminate scenarios worthy of more complex investigation, and to iteratively validate the models as they continue to be refined and extended. The paper discusses future efforts to refine, extend, and validate the models with more data and real data relative to physical (spatial-topographical and social inputs (staffing, patient care models, etc.. Real data obtained through proximity location and tracking system technologies is one example discussed.

  17. The acceptability of waiting times for elective general surgery and the appropriateness of prioritising patients

    Directory of Open Access Journals (Sweden)

    Knol Dirk L

    2007-02-01

    Full Text Available Abstract Background Problematic waiting lists in public health care threaten the equity and timeliness of care provision in several countries. This study assesses different stakeholders' views on the acceptability of waiting lists in health care, their preferences for priority care of patients, and their judgements on acceptable waiting times for surgical patients. Methods A questionnaire survey was conducted among 257 former patients (82 with varicose veins, 86 with inguinal hernia, and 89 with gallstones, 101 surgeons, 95 occupational physicians, and 65 GPs. Judgements on acceptable waiting times were assessed using vignettes of patients with varicose veins, inguinal hernia, and gallstones. Results Participants endorsed the prioritisation of patients based on clinical need, but not on ability to benefit. The groups had significantly different opinions (p Acceptable waiting times ranged between 2 and 25 weeks depending on the type of disorder (p Conclusion The explicit prioritisation of patients seems an accepted means for reducing the overall burden from waiting lists. The disagreement about appropriate prioritisation criteria and the need for uniformity, however, raises concern about equity when implementing prioritisation in daily practice. Single factor waiting time thresholds seem insufficient for securing timely care provision in the presence of long waiting lists as they do not account for the different consequences of waiting between patients.

  18. Mandatory waiting periods and biased abortion counseling in Central and Eastern Europe.

    Science.gov (United States)

    Hoctor, Leah; Lamačková, Adriana

    2017-11-01

    Several Central and Eastern European countries have recently enacted retrogressive laws and policies introducing new preconditions that women must fulfill before they can obtain legal abortion services. Mandatory waiting periods and biased counseling and information requirements are particularly common examples of these new prerequisites. The present article considers these requirements in light of international human rights standards and public health guidelines, and outlines the manner in which, by imposing regressive barriers on women's access to legal abortion services, these new laws and policies undermine women's health and well-being, fail to respect women's human rights, and reinforce harmful gender stereotypes and abortion stigma. © 2017 International Federation of Gynecology and Obstetrics.

  19. Waiting Endurance Time Estimation of Electric Two-Wheelers at Signalized Intersections

    Directory of Open Access Journals (Sweden)

    Mei Huan

    2014-01-01

    Full Text Available The paper proposed a model for estimating waiting endurance times of electric two-wheelers at signalized intersections using survival analysis method. Waiting duration times were collected by video cameras and they were assigned as censored and uncensored data to distinguish between normal crossing and red-light running behavior. A Cox proportional hazard model was introduced, and variables revealing personal characteristics and traffic conditions were defined as covariates to describe the effects of internal and external factors. Empirical results show that riders do not want to wait too long to cross intersections. As signal waiting time increases, electric two-wheelers get impatient and violate the traffic signal. There are 12.8% of electric two-wheelers with negligible wait time. 25.0% of electric two-wheelers are generally nonrisk takers who can obey the traffic rules after waiting for 100 seconds. Half of electric two-wheelers cannot endure 49.0 seconds or longer at red-light phase. Red phase time, motor vehicle volume, and conformity behavior have important effects on riders’ waiting times. Waiting endurance times would decrease with the longer red-phase time, the lower traffic volume, or the bigger number of other riders who run against the red light. The proposed model may be applicable in the design, management and control of signalized intersections in other developing cities.

  20. Waiting endurance time estimation of electric two-wheelers at signalized intersections.

    Science.gov (United States)

    Huan, Mei; Yang, Xiao-bao

    2014-01-01

    The paper proposed a model for estimating waiting endurance times of electric two-wheelers at signalized intersections using survival analysis method. Waiting duration times were collected by video cameras and they were assigned as censored and uncensored data to distinguish between normal crossing and red-light running behavior. A Cox proportional hazard model was introduced, and variables revealing personal characteristics and traffic conditions were defined as covariates to describe the effects of internal and external factors. Empirical results show that riders do not want to wait too long to cross intersections. As signal waiting time increases, electric two-wheelers get impatient and violate the traffic signal. There are 12.8% of electric two-wheelers with negligible wait time. 25.0% of electric two-wheelers are generally nonrisk takers who can obey the traffic rules after waiting for 100 seconds. Half of electric two-wheelers cannot endure 49.0 seconds or longer at red-light phase. Red phase time, motor vehicle volume, and conformity behavior have important effects on riders' waiting times. Waiting endurance times would decrease with the longer red-phase time, the lower traffic volume, or the bigger number of other riders who run against the red light. The proposed model may be applicable in the design, management and control of signalized intersections in other developing cities.

  1. Waiting Time from Diagnosis to Treatment has no Impact on Survival in Patients with Esophageal Cancer

    NARCIS (Netherlands)

    Visser, E.; Leeftink, Anne Greetje; van Rossum, P.S.N.; Siesling, Sabine; van Hillegersberg, R.; Ruurda, J.P.

    2016-01-01

    Background Waiting time from diagnosis to treatment has emerged as an important quality indicator in cancer care. This study was designed to determine the impact of waiting time on long-term outcome of patients with esophageal cancer who are treated with neoadjuvant therapy followed by surgery or

  2. Client waiting time in an urban primary health care centre in Lagos ...

    African Journals Online (AJOL)

    Background: Primary Health Care is the usual entry point into the health system and has the potential to touch the lives of most people. However one of the reasons for poor uptake of health services at primary health care facilities in Nigeria is long waiting time. This study was carried out to assess client waiting time and ...

  3. Effects of Wait Time When Communicating with Children Who Have Sensory and Additional Disabilities

    Science.gov (United States)

    Johnson, Nicole; Parker, Amy T.

    2013-01-01

    Introduction: This study utilized wait-time procedures to determine if they are effective in helping children with deafblindness or multiple disabilities that include a visual impairment communicate in their home. Methods: A single subject with an alternating treatment design was used for the study. Zero- to one-second wait time was utilized…

  4. Determinants of Patient Waiting Time in the General Outpatient ...

    African Journals Online (AJOL)

    obtaining services and keeping patients waiting unnecessarily can be a cause of stress for both .... Simple random sampling was done for the first two patients to get the starting ... record clerks (12% [9/76]), and jumping of queue by patients.

  5. Research on the waiting time of passengers and escalator energy consumption at the railway station

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Wei-wu; Liu, Xiao-yan; Li, Liqing; Shi, Xiangnan; Zhou, Chenn Q. [School of Energy Science and Engineering, Central South University, Changsha 410083 (China)

    2009-12-15

    Based on the Little Formula and the classical queuing model of multi-channel M vertical stroke D vertical stroke n, the relation of the average queue length, the maximum waiting time and the escalator service intensity were identified and the waiting time simulation model was established. With the passenger delivery data at A railway station in China and the probability distribution model of waiting time, a detailed analysis was made on the escalator allocation, power and energy consumption on holidays, ordinary working days and the largest-passengers-volume days; meanwhile, the fixed and variable energy consumption were compared and studied when the waiting time are 5, 10 and 30 s. The result shows that the waiting time settings affect the allocation and the energy consumption of the escalators and the fixed energy consumption takes 70%. (author)

  6. [Waiting time for the first colposcopic examination in women with abnormal Papanicolaou test].

    Science.gov (United States)

    Nascimento, Maria Isabel do; Rabelo, Irene Machado Moraes Alvarenga; Cardoso, Fabrício Seabra Polidoro; Musse, Ricardo Neif Vieira

    2015-08-01

    To evaluate the waiting times before obtaining the first colposcopic examination for women with abnormal Papanicolaou smears. Retrospective cohort study conducted on patients who required a colposcopic examination to clarify an abnormal pap test, between 2002 January and 2008 August, in a metropolitan region of Brazil. The waiting times were defined as: Total Waiting Time (interval between the date of the pap test result and the date of the first colposcopic examination); Partial A Waiting Time (interval between the date of the pap test result and the date of referral); Partial B Waiting Time (interval between the date of referral and the date of the first colposcopic examination). Means, medians, relative and absolute frequencies were calculated. The Kruskal-Wallis test and Pearson's chi-square test were used to determine statistical significance. A total of 1,544 women with mean of age of 34 years (SD=12.6 years) were analyzed. Most of them had access to colposcopic examination within 30 days (65.8%) or 60 days (92.8%) from referral. Mean Total Waiting Time, Partial A Waiting Time, and Partial B Waiting Time were 94.5 days (SD=96.8 days), 67.8 days (SD=95.3 days) and 29.2 days (SD=35.1 days), respectively. A large part of the women studied had access to colposcopic examination within 60 days after referral, but Total waiting time was long. Measures to reduce the waiting time for obtaining the first colposcopic examination can help to improve the quality of care in the context of cervical cancer control in the region, and ought to be addressed at the phase between the date of the pap test results and the date of referral to the teaching hospital.

  7. Space, place and (waiting) time: reflections on health policy and politics.

    Science.gov (United States)

    Sheard, Sally

    2018-02-19

    Health systems have repeatedly addressed concerns about efficiency and equity by employing trans-national comparisons to draw out the strengths and weaknesses of specific policy initiatives. This paper demonstrates the potential for explicit historical analysis of waiting times for hospital treatment to add value to spatial comparative methodologies. Waiting times and the size of the lists of waiting patients have become key operational indicators. In the United Kingdom, as National Health Service (NHS) financial pressures intensified from the 1970s, waiting times have become a topic for regular public and political debate. Various explanations for waiting times include the following: hospital consultants manipulate NHS waiting lists to maintain their private practice; there is under-investment in the NHS; and available (and adequate) resources are being used inefficiently. Other countries have also experienced ongoing tensions between the public and private delivery of universal health care in which national and trans-national comparisons of waiting times have been regularly used. The paper discusses the development of key UK policies, and provides a limited Canadian comparative perspective, to explore wider issues, including whether 'waiting crises' were consciously used by policymakers, especially those brought into government to implement new economic and managerial strategies, to diminish the autonomy and authority of the medical professional in the hospital environment.

  8. Waiting times for prostate cancer diagnosis in KwaZulu-Natal, South ...

    African Journals Online (AJOL)

    prostate cancer (an elevated prostate-specific antigen level or abnormal findings on digital rectal examination) wait to have a prostate biopsy. Objectives. To improve the overall efficiency of the prostate biopsy service offered at St Aidan's Regional Hospital, Durban, SA, by quantifying the burden of disease and waiting times ...

  9. Reading of Waiting, Time and Social Change in S. N. A. Agoro's ...

    African Journals Online (AJOL)

    It is against this backdrop that we attempt to explore the depiction and treatment of waiting, time and social change in the dramatic universe of existentialism created by some playwrights who have not been given scholarly attention. The study shall therefore undertake a dialectical consideration of the concept of waiting and ...

  10. A RFID-based JIT Application for Least Waiting Time for Dynamic Smart Diet Customers

    Directory of Open Access Journals (Sweden)

    Chen Long-Fei

    2017-01-01

    Full Text Available Waiting in queue is part of everyone’s life. A day may include several different waiting in queue. Waiting in line is always a bit of phenomena for a prosperous restaurant at dinner time. How to manage the queues and keep their feet into customers is the operating challenge facing everyone manager. In addition, rising energy costs and growing demand for protection of the environment call for a shorter waiting queue. Thus, we devise a dynamic smart diet App manager to reduce customer waiting time through radio frequency identification (RFID and just in time (JIT principle to reduce inventory of restaurant food materials, thereby increasing customer satisfaction and loyalty, and improving revenue and social responsibility.

  11. General practice cooperatives: long waiting times for home visits due to long distances?

    Science.gov (United States)

    Giesen, Paul; van Lin, Nieke; Mokkink, Henk; van den Bosch, Wil; Grol, Richard

    2007-02-12

    The introduction of large-scale out-of-hours GP cooperatives has led to questions about increased distances between the GP cooperatives and the homes of patients and the increasing waiting times for home visits in urgent cases. We studied the relationship between the patient's waiting time for a home visit and the distance to the GP cooperative. Further, we investigated if other factors (traffic intensity, home visit intensity, time of day, and degree of urgency) influenced waiting times. Cross-sectional study at four GP cooperatives. We used variance analysis to calculate waiting times for various categories of traffic intensity, home visit intensity, time of day, and degree of urgency. We used multiple logistic regression analysis to calculate to what degree these factors affected the ability to meet targets in urgent cases. The average waiting time for 5827 consultations was 30.5 min. Traffic intensity, home visit intensity, time of day and urgency of the complaint all seemed to affect waiting times significantly. A total of 88.7% of all patients were seen within 1 hour. In the case of life-threatening complaints (U1), 68.8% of the patients were seen within 15 min, and 95.6% of those with acute complaints (U2) were seen within 1 hour. For patients with life-threatening complaints (U1) the percentage of visits that met the time target of 15 minutes decreased from 86.5% (less than 2.5 km) to 16.7% (equals or more than 20 km). Although home visits waiting times increase with increasing distance from the GP cooperative, it appears that traffic intensity, home visit intensity, and urgency also influence waiting times. For patients with life-threatening complaints waiting times increase sharply with the distance.

  12. Survey of Access to GastroEnterology in Canada: The SAGE wait times program

    Science.gov (United States)

    Leddin, Desmond; Bridges, Ronald J; Morgan, David G; Fallone, Carlo; Render, Craig; Plourde, Victor; Gray, Jim; Switzer, Connie; McHattie, Jim; Singh, Harminder; Walli, Eric; Murray, Iain; Nestel, Anthony; Sinclair, Paul; Chen, Ying; Irvine, E Jan

    2010-01-01

    BACKGROUND: Assessment of current wait times for specialist health services in Canada is a key method that can assist government and health care providers to plan wisely for future health needs. These data are not readily available. A method to capture wait time data at the time of consultation or procedure has been developed, which should be applicable to other specialist groups and also allows for assessment of wait time trends over intervals of years. METHODS: In November 2008, gastroenterologists across Canada were asked to complete a questionnaire (online or by fax) that included personal demographics and data from one week on at least five consecutive new consultations and five consecutive procedure patients who had not previously undergone a procedure for the same indication. Wait times were collected for 18 primary indications and results were then compared with similar survey data collected in 2005. RESULTS: The longest wait times observed were for screening colonoscopy (201 days) and surveillance of previous colon cancer or polyps (272 days). The shortest wait times were for cancer-likely based on imaging or physical examination (82 days), severe or rapidly progressing dysphagia or odynophagia (83 days), documented iron-deficiency anemia (90 days) and dyspepsia with alarm symptoms (99 days). Compared with 2005 data, total wait times in 2008 were lengthened overall (127 days versus 155 days; Pgastroenterology services continue to exceed consensus conference recommended targets and have significantly worsened since 2005. PMID:20186352

  13. Adjusting patients streaming initiated by a wait time threshold in emergency department for minimizing opportunity cost.

    Science.gov (United States)

    Kim, Byungjoon B J; Delbridge, Theodore R; Kendrick, Dawn B

    2017-07-10

    Purpose Two different systems for streaming patients were considered to improve efficiency measures such as waiting times (WTs) and length of stay (LOS) for a current emergency department (ED). A typical fast track area (FTA) and a fast track with a wait time threshold (FTW) were designed and compared effectiveness measures from the perspective of total opportunity cost of all patients' WTs in the ED. The paper aims to discuss these issues. Design/methodology/approach This retrospective case study used computerized ED patient arrival to discharge time logs (between July 1, 2009 and June 30, 2010) to build computer simulation models for the FTA and fast track with wait time threshold systems. Various wait time thresholds were applied to stream different acuity-level patients. National average wait time for each acuity level was considered as a threshold to stream patients. Findings The fast track with a wait time threshold (FTW) showed a statistically significant shorter total wait time than the current system or a typical FTA system. The patient streaming management would improve the service quality of the ED as well as patients' opportunity costs by reducing the total LOS in the ED. Research limitations/implications The results of this study were based on computer simulation models with some assumptions such as no transfer times between processes, an arrival distribution of patients, and no deviation of flow pattern. Practical implications When the streaming of patient flow can be managed based on the wait time before being seen by a physician, it is possible for patients to see a physician within a tolerable wait time, which would result in less crowded in the ED. Originality/value A new streaming scheme of patients' flow may improve the performance of fast track system.

  14. Public views on a wait time management initiative: a matter of communication.

    Science.gov (United States)

    Bruni, Rebecca A; Laupacis, Andreas; Levinson, Wendy; Martin, Douglas K

    2010-08-05

    Many countries have tried to reduce waiting times for health care through formal wait time reduction strategies. Our paper describes views of members of the public about a wait time management initiative--the Ontario Wait Time Strategy (OWTS) (Canada). Scholars and governmental reports have advocated for increased public involvement in wait time management. We provide empirically derived recommendations for public engagement in a wait time management initiative. Two qualitative studies: 1) an analysis of all emails sent by the public to the (OWTS) email address; and 2) in-depth interviews with members of the Ontario public. Email correspondents and interview participants supported the intent of the OWTS. However they wanted more information about the Strategy and its actions. Interview participants did not feel they were sufficiently made aware of the Strategy and email correspondents requested additional information beyond what was offered on the Strategy's website. Moreover, the email correspondents believed that some of the information that was provided on the Strategy's website and through the media was inaccurate, misleading, and even dishonest. Interview participants strongly supported public involvement in the OWTS priority setting. Findings suggest the public wanted increased communication from and with the OWTS. Effective communication can facilitate successful public engagement, and in turn fair and legitimate priority setting. Based on the study's findings we developed concrete recommendations for improving public involvement in wait time management.

  15. Public views on a wait time management initiative: a matter of communication

    Directory of Open Access Journals (Sweden)

    Laupacis Andreas

    2010-08-01

    Full Text Available Abstract Background Many countries have tried to reduce waiting times for health care through formal wait time reduction strategies. Our paper describes views of members of the public about a wait time management initiative - the Ontario Wait Time Strategy (OWTS (Canada. Scholars and governmental reports have advocated for increased public involvement in wait time management. We provide empirically derived recommendations for public engagement in a wait time management initiative. Methods Two qualitative studies: 1 an analysis of all emails sent by the public to the (OWTS email address; and 2 in-depth interviews with members of the Ontario public. Results Email correspondents and interview participants supported the intent of the OWTS. However they wanted more information about the Strategy and its actions. Interview participants did not feel they were sufficiently made aware of the Strategy and email correspondents requested additional information beyond what was offered on the Strategy's website. Moreover, the email correspondents believed that some of the information that was provided on the Strategy's website and through the media was inaccurate, misleading, and even dishonest. Interview participants strongly supported public involvement in the OWTS priority setting. Conclusions Findings suggest the public wanted increased communication from and with the OWTS. Effective communication can facilitate successful public engagement, and in turn fair and legitimate priority setting. Based on the study's findings we developed concrete recommendations for improving public involvement in wait time management.

  16. Experiences of counselling in the emergency department during the waiting period: importance of family participation.

    Science.gov (United States)

    Paavilainen, Eija; Salminen-Tuomaala, Mari; Kurikka, Sirpa; Paussu, Paula

    2009-08-01

    To describe patients' experiences of counselling, defined as information giving and advice by nursing staff, in the emergency department. A particular focus was on the waiting period and on the importance of family participation in counselling. Counselling is a widely studied topic in nursing. Too little is known about counselling in emergency departments and especially about participation of family members and suitability of counselling for the patient's life situation. Descriptive quantitative study. Data were collected by questionnaires from patients (n = 107) visiting a hospital emergency department. The data were subjected to statistical analysis. Forty-two per cent of patients arrived at the emergency department with a family member: spouse or cohabiting partner, mother, father or daughter. Patients were fairly satisfied with the counselling. The presence of a family member was important to the majority of patients (75%). About half of the patients wanted information concerning their illness, condition and treatment to be given to their family members. Those visiting the department with a family member were more satisfied with counselling and felt that it promoted their participation in care. It is to encourage patients' family members to participate in counselling situations in emergency departments. However, the type of information passed on to family members should be carefully discussed and prepared. Patients' family members seem to be important partners in counselling situations. The presence of family members supports patients in the emergency department during the waiting period and helps them orientate in their situation. When family members are present, issues which patients wish to discuss should be carefully planned. Family presence should be encouraged in emergency departments.

  17. Shorter Perceived Outpatient MRI Wait Times Associated With Higher Patient Satisfaction.

    Science.gov (United States)

    Holbrook, Anna; Glenn, Harold; Mahmood, Rabia; Cai, Qingpo; Kang, Jian; Duszak, Richard

    2016-05-01

    The aim of this study was to assess differences in perceived versus actual wait times among patients undergoing outpatient MRI examinations and to correlate those times with patient satisfaction. Over 15 weeks, 190 patients presenting for outpatient MR in a radiology department in which "patient experience" is one of the stated strategic priorities were asked to (1) estimate their wait times for various stages in the imaging process and (2) state their satisfaction with their imaging experience. Perceived times were compared with actual electronic time stamps. Perceived and actual times were compared and correlated with standardized satisfaction scores using Kendall τ correlation. The mean actual wait time between patient arrival and examination start was 53.4 ± 33.8 min, whereas patients perceived a mean wait time of 27.8 ± 23.1 min, a statistically significant underestimation of 25.6 min (P perceived wait times at all points during patient encounters were correlated with higher satisfaction scores (P perceived and actual wait times were both correlated with higher satisfaction scores. As satisfaction surveys play a larger role in an environment of metric transparency and value-based payments, better understanding of such factors will be increasingly important. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  18. The ecology of the patient visit: physical attractiveness, waiting times, and perceived quality of care.

    Science.gov (United States)

    Becker, Franklin; Douglass, Stephanie

    2008-01-01

    This study examined the relationship between the attractiveness of the physical environment of healthcare facilities and patient perceptions of quality, service, and waiting time through systematic observations and patient satisfaction surveys at 7 outpatient practices at Weill Cornell Medical Center. Findings indicate positive correlations between more attractive environments and higher levels of perceived quality, satisfaction, staff interaction, and reduction of patient anxiety. The comparison of actual observed time and patients' perception of time showed that patients tend to overestimate shorter waiting times and underestimate longer waiting times in both the waiting area and the examination room. Further examinations of the way outpatient-practice environments impact patient and staff perceptions and how those perceptions impact behavior and medical outcomes are suggested.

  19. Act-and-wait time-delayed feedback control of nonautonomous systems

    Science.gov (United States)

    Pyragas, Viktoras; Pyragas, Kestutis

    2016-07-01

    Act-and-wait modification of a time-delayed feedback control (TDFC) algorithm is proposed to stabilize unstable periodic orbits in nonautonomous dynamical systems. Due to periodical switching on and off the control perturbation, an infinite-dimensional function space of the TDFC system is reduced to the finite-dimensional state space. As a result the number of Floquet exponents defining the stability of the controlled orbit remains the same as for the control-free system. The values of these exponents can be effectively manipulated by the variation of control parameters. We demonstrate the advantages of the modification for the chaotic nonautonomous Duffing oscillator with diagonal and nondiagonal control matrices. In both cases very deep minima of the spectral abscissa of Floquet exponents have been attained. The advantage of the modification is particularly remarkable for the nondiagonal coupling; in this case the conventional TDFC fails, whereas the modified version works.

  20. Asymptotic inference for waiting times and patiences in queues with abandonment

    DEFF Research Database (Denmark)

    Gorst-Rasmussen, Anders; Hansen, Martin Bøgsted

    Motivated by applications in call center management, we propose a framework based on empirical process techniques for inference about the waiting time and patience distribution in multiserver queues with abandonment. The framework rigorises heuristics based on survival analysis of independent...

  1. Asymptotic inference for waiting times and patiences in queues with abandonment

    DEFF Research Database (Denmark)

    Gorst-Rasmussen, Anders; Hansen, Martin Bøgsted

    2009-01-01

    Motivated by applications in call center management, we propose a framework based on empirical process techniques for inference about waiting time and patience distributions in multiserver queues with abandonment. The framework rigorises heuristics based on survival analysis of independent...

  2. Health care justice and its implications for current policy of a mandatory waiting period for elective tubal sterilization.

    Science.gov (United States)

    Moaddab, Amirhossein; McCullough, Laurence B; Chervenak, Frank A; Fox, Karin A; Aagaard, Kjersti Marie; Salmanian, Bahram; Raine, Susan P; Shamshirsaz, Alireza A

    2015-06-01

    Tubal sterilization during the immediate postpartum period is 1 of the most common forms of contraception in the United States. This time of the procedure has the advantage of 1-time hospitalization, which results in ease and convenience for the woman. The US Collaborative Review of Sterilization Study indicates the high efficacy and effectiveness of postpartum tubal sterilization. Oral and written informed consent is the ethical and legal standard for the performance of elective tubal sterilization for permanent contraception for all patients, regardless of source of payment. Current health care policy and practice regarding elective tubal sterilization for Medicaid beneficiaries places a unique requirement on these patients and their obstetricians: a mandatory waiting period. This requirement originates in decades-old legislation, which we briefly describe. We then introduce the concept of health care justice in professional obstetric ethics and explain how it originates in the ethical concepts of medicine as a profession and of being a patient and its deontologic and consequentialist dimensions. We next identify the implications of health care justice for the current policy of a mandatory 30-day waiting period. We conclude that Medicaid policy allocates access to elective tubal sterilization differently, based on source of payment and gender, which violates health care justice in both its deontologic and consequentialist dimensions. Obstetricians should invoke health care justice in women's health care as the basis for advocacy for needed change in law and health policy, to eliminate health care injustice in women's access to elective tubal sterilization. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Waiting room time: An opportunity for parental oral health education.

    Science.gov (United States)

    Soussou, Randa; Aleksejūnienė, Jolanta; Harrison, Rosamund

    2017-09-14

    The UBC Children's Dental Program (CDP) has provided free dental treatments to underserved low-income children, but its preventive component needs to be enhanced. The study aims were: 1) to develop a "waiting-room based" dental education program engaging caregivers of these children, and 2) to assess the program's feasibility, acceptability and effectiveness. In preparation, a situational analysis (SA) included structured interviews with caregivers, and with various stakeholders (e.g., dental students, instructors, health authority) involved in the CDP program. Based on the SA, caregiver-centered education was designed using an interactive power point presentation; after the presentation, each caregiver set personalized goals for modifying his/her child's dental behaviours. Evaluation of the program was done with follow-up telephone calls; the program's effectiveness was assessed by comparing before/after proportions of caregivers brushing their child's teeth, children brushing teeth in the morning and evening, children eating sugar-containing snacks, and children drinking sugar-containing drinks. The program proved to be easy to implement (feasible) and the recruitment rate was 99% (acceptable). The follow-up rate was 81%. The SA identified that the caregivers' knowledge about caries etiology and prevention was limited. All recruited caregivers completed the educational session and set goals for their family. The evaluation demonstrated an increase in caregiver-reported short-term diet and oral self-care behaviours of their children. A dental education program engaging caregivers in the waiting room was a feasible, acceptable and promising strategy for improving short-term dental behaviours of children.

  4. Public reporting on quality, waiting times and patient experience in 11 high-income countries

    OpenAIRE

    Rechel, Bernd; McKee, Martin; Haas, Marion; Marchildon, Gregory P; Bousquet, Frederic; Blümel, Miriam; Geissler, Alexander; van Ginneken, Ewout; Ashton, Toni; Saunes, Ingrid Sperre; Anell, Anders; Quentin, Wilm; Saltman, Richard; Culler, Steven; Barnes, Andrew

    2016-01-01

    : This article maps current approaches to public reporting on waiting times, patient experience and aggregate measures of quality and safety in 11 high-income countries (Australia, Canada, England, France, Germany, Netherlands, New Zealand, Norway, Sweden, Switzerland and the United States). Using a questionnaire-based survey of key national informants, we found that the data most commonly made available to the public are on waiting times for hospital treatment, being reported for major hospi...

  5. Intake of wine, beer and spirits and waiting time to pregnancy

    DEFF Research Database (Denmark)

    Juhl, Mette; Olsen, Jørn; Andersen, Anne-Marie Nybo

    2003-01-01

    A high intake of alcohol may prolong waiting time to pregnancy, whereas a moderate intake may have no or perhaps even a positive effect on fecundity. In previous studies on fecundity, different types of beverages have not been taken into consideration, although moderate wine drinkers appear to have...... fewer strokes, lung and digestive tract cancers, and overall mortality than both abstainers and moderate drinkers of beer or spirits. We examined the association between different types of alcoholic beverages and waiting time to pregnancy....

  6. Discrimination in waiting times by insurance type and financial soundness of German acute care hospitals.

    Science.gov (United States)

    Schwierz, Christoph; Wübker, Achim; Wübker, Ansgar; Kuchinke, Björn A

    2011-10-01

    This paper shows that patients with private health insurance (PHI) are being offered significantly shorter waiting times than patients with statutory health insurance (SHI) in German acute hospital care. This behavior may be driven by the higher expected profitability of PHI relative to SHI holders. Further, we find that hospitals offering private insurees shorter waiting times when compared with SHI holders have a significantly better financial performance than those abstaining from or with less discrimination.

  7. Using Queuing Theory and Simulation Modelling to Reduce Waiting Times in An Iranian Emergency Department

    OpenAIRE

    Haghighinejad, Hourvash Akbari; Kharazmi, Erfan; Hatam, Nahid; Yousefi, Sedigheh; Hesami, Seyed Ali; Danaei, Mina; Askarian, Mehrdad

    2016-01-01

    Background: Hospital emergencies have an essential role in health care systems. In the last decade, developed countries have paid great attention to overcrowding crisis in emergency departments. Simulation analysis of complex models for which conditions will change over time is much more effective than analytical solutions and emergency department (ED) is one of the most complex models for analysis. This study aimed to determine the number of patients who are waiting and waiting time in emerg...

  8. Waiting time distribution revealing the internal spin dynamics in a double quantum dot

    Science.gov (United States)

    Ptaszyński, Krzysztof

    2017-07-01

    Waiting time distribution and the zero-frequency full counting statistics of unidirectional electron transport through a double quantum dot molecule attached to spin-polarized leads are analyzed using the quantum master equation. The waiting time distribution exhibits a nontrivial dependence on the value of the exchange coupling between the dots and the gradient of the applied magnetic field, which reveals the oscillations between the spin states of the molecule. The zero-frequency full counting statistics, on the other hand, is independent of the aforementioned quantities, thus giving no insight into the internal dynamics. The fact that the waiting time distribution and the zero-frequency full counting statistics give a nonequivalent information is associated with two factors. Firstly, it can be explained by the sensitivity to different timescales of the dynamics of the system. Secondly, it is associated with the presence of the correlation between subsequent waiting times, which makes the renewal theory, relating the full counting statistics and the waiting time distribution, no longer applicable. The study highlights the particular usefulness of the waiting time distribution for the analysis of the internal dynamics of mesoscopic systems.

  9. The impact of different prioritisation policies on waiting times: case studies of Norway and Scotland.

    Science.gov (United States)

    Januleviciute, Jurgita; Askildsen, Jan Erik; Kaarboe, Oddvar; Holmås, Tor Helge; Sutton, Matt

    2013-11-01

    We investigate the distributional consequences of two different waiting times initiatives, one in Norway, and one in Scotland. The primary focus of Scotland's recent waiting time reforms, introduced in 2003, and modified in 2005 and 2007, has been on reducing maximum waiting times through the imposition of high profile national targets accompanied by increases in resources. In Norway, the focus of the reform introduced in September 2004, has been on assigning patients referred to hospital a maximum waiting time based on disease severity, the expected benefit and the cost-effectiveness of the treatment. We use large, national administrative datasets from before and after each of these reforms and assign priority groups based on the maximum waiting times stipulated in medical guidelines. The analysis shows that the lowest priority patients benefited most from both reforms. This was at the cost of longer waiting times for patients that should have been given higher priority in Norway, while Scotland's high priority patients remained unaffected. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Waiting when hospitalised

    DEFF Research Database (Denmark)

    Ludvigsen, Mette Spliid

    2004-01-01

    on participating observations during a period of one and a half year. The material is analysed with inspiration from Mattingly's ideas of narrative and time. ConclusionsAlthough waiting times is not a clinically serious problem, the satisfaction levels of patients with the care they receive have become...... increasingly important in today's health care environment. The indicative conclusions form this study suggest that nurses play an important role in ensuring that patients are satisfied and receive quality care when waiting....

  11. Using Queuing Theory and Simulation Modelling to Reduce Waiting Times in An Iranian Emergency Department.

    Science.gov (United States)

    Haghighinejad, Hourvash Akbari; Kharazmi, Erfan; Hatam, Nahid; Yousefi, Sedigheh; Hesami, Seyed Ali; Danaei, Mina; Askarian, Mehrdad

    2016-01-01

    Hospital emergencies have an essential role in health care systems. In the last decade, developed countries have paid great attention to overcrowding crisis in emergency departments. Simulation analysis of complex models for which conditions will change over time is much more effective than analytical solutions and emergency department (ED) is one of the most complex models for analysis. This study aimed to determine the number of patients who are waiting and waiting time in emergency department services in an Iranian hospital ED and to propose scenarios to reduce its queue and waiting time. This is a cross-sectional study in which simulation software (Arena, version 14) was used. The input information was extracted from the hospital database as well as through sampling. The objective was to evaluate the response variables of waiting time, number waiting and utilization of each server and test the three scenarios to improve them. Running the models for 30 days revealed that a total of 4088 patients left the ED after being served and 1238 patients waited in the queue for admission in the ED bed area at end of the run (actually these patients received services out of their defined capacity). The first scenario result in the number of beds had to be increased from 81 to179 in order that the number waiting of the "bed area" server become almost zero. The second scenario which attempted to limit hospitalization time in the ED bed area to the third quartile of the serving time distribution could decrease the number waiting to 586 patients. Doubling the bed capacity in the emergency department and consequently other resources and capacity appropriately can solve the problem. This includes bed capacity requirement for both critically ill and less critically ill patients. Classification of ED internal sections based on severity of illness instead of medical specialty is another solution.

  12. Discovering the impact of preceding units' characteristics on the wait time of cardiac surgery unit from statistic data.

    Science.gov (United States)

    Liu, Jiming; Tao, Li; Xiao, Bo

    2011-01-01

    Prior research shows that clinical demand and supplier capacity significantly affect the throughput and the wait time within an isolated unit. However, it is doubtful whether characteristics (i.e., demand, capacity, throughput, and wait time) of one unit would affect the wait time of subsequent units on the patient flow process. Focusing on cardiac care, this paper aims to examine the impact of characteristics of the catheterization unit (CU) on the wait time of cardiac surgery unit (SU). This study integrates published data from several sources on characteristics of the CU and SU units in 11 hospitals in Ontario, Canada between 2005 and 2008. It proposes a two-layer wait time model (with each layer representing one unit) to examine the impact of CU's characteristics on the wait time of SU and test the hypotheses using the Partial Least Squares-based Structural Equation Modeling analysis tool. Results show that: (i) wait time of CU has a direct positive impact on wait time of SU (β = 0.330, p relationships among different characteristics (except for the effect of throughput on wait time in SU). Characteristics of CU have direct and indirect impacts on wait time of SU. Specifically, demand and wait time of preceding unit are good predictors for wait time of subsequent units. This suggests that considering such cross-unit effects is necessary when alleviating wait time in a health care system. Further, different patient risk profiles may affect wait time in different ways (e.g., positive or negative effects) within SU. This implies that the wait time management should carefully consider the relationship between priority triage and risk stratification, especially for cardiac surgery.

  13. Discovering the impact of preceding units' characteristics on the wait time of cardiac surgery unit from statistic data.

    Directory of Open Access Journals (Sweden)

    Jiming Liu

    Full Text Available INTRODUCTION: Prior research shows that clinical demand and supplier capacity significantly affect the throughput and the wait time within an isolated unit. However, it is doubtful whether characteristics (i.e., demand, capacity, throughput, and wait time of one unit would affect the wait time of subsequent units on the patient flow process. Focusing on cardiac care, this paper aims to examine the impact of characteristics of the catheterization unit (CU on the wait time of cardiac surgery unit (SU. METHODS: This study integrates published data from several sources on characteristics of the CU and SU units in 11 hospitals in Ontario, Canada between 2005 and 2008. It proposes a two-layer wait time model (with each layer representing one unit to examine the impact of CU's characteristics on the wait time of SU and test the hypotheses using the Partial Least Squares-based Structural Equation Modeling analysis tool. RESULTS: Results show that: (i wait time of CU has a direct positive impact on wait time of SU (β = 0.330, p < 0.01; (ii capacity of CU has a direct positive impact on demand of SU (β = 0.644, p < 0.01; (iii within each unit, there exist significant relationships among different characteristics (except for the effect of throughput on wait time in SU. CONCLUSION: Characteristics of CU have direct and indirect impacts on wait time of SU. Specifically, demand and wait time of preceding unit are good predictors for wait time of subsequent units. This suggests that considering such cross-unit effects is necessary when alleviating wait time in a health care system. Further, different patient risk profiles may affect wait time in different ways (e.g., positive or negative effects within SU. This implies that the wait time management should carefully consider the relationship between priority triage and risk stratification, especially for cardiac surgery.

  14. [Reducing patient waiting time for the outpatient phlebotomy service using six sigma].

    Science.gov (United States)

    Kim, Yu Kyung; Song, Kyung Eun; Lee, Won Kil

    2009-04-01

    One of the challenging issues of the outpatient phlebotomy services at most hospitals is that patients have a long wait. The outpatient phlebotomy team of Kyungpook National University Hospital applied six sigma breakthrough methodologies to reduce the patient waiting time. The DMAIC (Define, Measure, Analyze, Improve, and Control) model was employed to approach the project. Two hundred patients visiting the outpatient phlebotomy section were asked to answer the questionnaires at inception of the study to ascertain root causes. After correction, we surveyed 285 patients for same questionnaires again to follow-up the effects. A defect was defined as extending patient waiting time so long and at the beginning of the project, the performance level was 2.61 sigma. Using fishbone diagram, all the possible reasons for extending patient waiting time were captured, and among them, 16 causes were proven to be statistically significant. Improvement plans including a new receptionist, automatic specimen transport system, and adding one phlebotomist were put into practice. As a result, the number of patients waited more than 5 min significantly decreased, and the performance level reached 3.0 sigma in December 2007 and finally 3.35 sigma in July 2008. Applying the six sigma, the performance level of waiting times for blood drawing exceeding five minutes were improved from 2.61 sigma to 3.35 sigma.

  15. Waiting times for diagnosis and treatment of head and neck cancer in Denmark in 2010 compared to 1992 and 2002

    DEFF Research Database (Denmark)

    Lyhne, N M; Christensen, A; Alanin, M C

    2013-01-01

    BACKGROUND AND AIM: Significant tumour progression was observed during waiting time for treatment of head and neck cancer. To reduce waiting times, a Danish national policy of fast track accelerated clinical pathways was introduced in 2007. This study describes changes in waiting time and the pot......BACKGROUND AND AIM: Significant tumour progression was observed during waiting time for treatment of head and neck cancer. To reduce waiting times, a Danish national policy of fast track accelerated clinical pathways was introduced in 2007. This study describes changes in waiting time...... and the potential influence of fast track by comparing waiting times in 2010 to 2002 and 1992. METHODS: Charts of all new patients diagnosed with squamous cell carcinoma of the oral cavity, pharynx and larynx at the five Danish head and neck oncology centres from January to April 2010 (n=253) were reviewed...

  16. Determinants of variability in waiting times for radiotherapy in the treatment of breast cancer

    International Nuclear Information System (INIS)

    Bouche, Gauthier; Ingrand, Isabelle; Mathoulin-Pelissier, Simone; Ingrand, Pierre; Breton-Callu, Christel; Migeot, Virginie

    2010-01-01

    Purpose: To examine psycho-social and geographic determinants of delay in starting radiotherapy in early invasive breast cancer patients. Material and methods: Waiting time was defined as the time elapsed until the beginning of radiotherapy, starting from the date of surgery (in absence of chemotherapy) or from the end of chemotherapy. Results: Eight hundred and ninety six women aged 24-89 took part in the study. Mean waiting times were 52 days (sd = 19) between surgery and radiotherapy and 31 days (sd = 14) between chemotherapy and radiotherapy. Differences between radiotherapy centres (p < 0.0001) accounted for 30% and 12%, respectively, of total variance in waiting times. Using a multivariate mixed analysis that took into account intra-centre correlation, the time between surgery and radiotherapy was shorter for young patients (p = 0.020), those who had sought information about their illness (p = 0.024) and those who had undergone surgery and radiotherapy in the same centre (p = 0.021). On the other hand, no patient characteristic was associated with the time between chemotherapy and radiotherapy. Conclusion: Centre is the major factor that explained longer waiting times in radiotherapy, emphasising the structural hypothesis. It is important to pursue initiatives to improve the organization within radiotherapy centres and then to verify that these initiatives have succeeded in shortening waiting times.

  17. Using Queuing Theory and Simulation Modelling to Reduce Waiting Times in An Iranian Emergency Department

    Directory of Open Access Journals (Sweden)

    Hourvash Akbari Haghighinejad

    2016-01-01

    Full Text Available Background: Hospital emergencies have an essential role in health care systems. In the last decade, developed countries have paid great attention to overcrowding crisis in emergency departments. Simulation analysis of complex models for which conditions will change over time is much more effective than analytical solutions and emergency department (ED is one of the most complex models for analysis. This study aimed to determine the number of patients who are waiting and waiting time in emergency department services in an Iranian hospital ED and to propose scenarios to reduce its queue and waiting time. Methods: This is a cross-sectional study in which simulation software (Arena, version 14 was used. The input information was extracted from the hospital database as well as through sampling. The objective was to evaluate the response variables of waiting time, number waiting and utilization of each server and test the three scenarios to improve them. Results: Running the models for 30 days revealed that a total of 4088 patients left the ED after being served and 1238 patients waited in the queue for admission in the ED bed area at end of the run (actually these patients received services out of their defined capacity. The first scenario result in the number of beds had to be increased from 81 to179 in order that the number waiting of the “bed area” server become almost zero. The second scenario which attempted to limit hospitalization time in the ED bed area to the third quartile of the serving time distribution could decrease the numberwaiting to 586 patients. Conclusion: Doubling the bed capacity in the emergency department and consequently other resources and capacity appropriately can solve the problem. This includes bed capacity requirement for both critically ill and less critically ill patients. Classification of ED internal sections based on severity of illness instead of medical specialty is another solution.

  18. Seasonality of service provision in hip and knee surgery: a possible contributor to waiting times? A time series analysis.

    Science.gov (United States)

    Upshur, Ross E G; Moineddin, Rahim; Crighton, Eric J; Mamdani, Muhammad

    2006-03-01

    The question of how best to reduce waiting times for health care, particularly surgical procedures such as hip and knee replacements is among the most pressing concern of the Canadian health care system. The objective of this study was to test the hypothesis that significant seasonal variation exists in the performance of hip and knee replacement surgery in the province of Ontario. We performed a retrospective, cross-sectional time series analysis examining all hip and knee replacement surgeries in people over the age of 65 in the province of Ontario, Canada between 1992 and 2002. The main outcome measure was monthly hospitalization rates per 100,000 population for all hip and knee replacements. There was a marked increase in the rate of hip and knee replacement surgery over the 10-year period as well as an increasing seasonal variation in surgeries. Highly significant (Fisher Kappa = 16.05, p Holidays and utilization caps appear to exert a significant influence on the rate of service provision. It is expected that waiting times for hip and knee replacement could be reduced by reducing seasonal fluctuations in service provision and benchmarking services to peak delivery. The results highlight the importance of system behaviour in seasonal fluctuation of service delivery.

  19. Seasonality of service provision in hip and knee surgery: A possible contributor to waiting times? A time series analysis

    Directory of Open Access Journals (Sweden)

    Upshur Ross EG

    2006-03-01

    Full Text Available Abstract Background The question of how best to reduce waiting times for health care, particularly surgical procedures such as hip and knee replacements is among the most pressing concern of the Canadian health care system. The objective of this study was to test the hypothesis that significant seasonal variation exists in the performance of hip and knee replacement surgery in the province of Ontario. Methods We performed a retrospective, cross-sectional time series analysis examining all hip and knee replacement surgeries in people over the age of 65 in the province of Ontario, Canada between 1992 and 2002. The main outcome measure was monthly hospitalization rates per 100 000 population for all hip and knee replacements. Results There was a marked increase in the rate of hip and knee replacement surgery over the 10-year period as well as an increasing seasonal variation in surgeries. Highly significant (Fisher Kappa = 16.05, p 2Autoreg = 0.85 seasonality was identified in the data. Conclusion Holidays and utilization caps appear to exert a significant influence on the rate of service provision. It is expected that waiting times for hip and knee replacement could be reduced by reducing seasonal fluctuations in service provision and benchmarking services to peak delivery. The results highlight the importance of system behaviour in seasonal fluctuation of service delivery.

  20. Posted wait times an added advantage to multi-facility systems?

    Science.gov (United States)

    2011-04-01

    Methodist Le Bonheur Healthcare in Memphis, TN, is investigating whether posting ED wait times via the internet can positively impact patient flow in the six EDs the health system operates in the Memphis region. The health system began posting wait times in August 2010, resulting in increases in ED volume ranging from 6% to 10%. The health system is monitoring ED arrivals by zip code to assess any impact on load balancing between its busy EDs. One marketing challenge is that a competitor is posting ED wait times as well, but it is posting the time it takes for a patient to be placed in a bed as opposed to the door-to-provider time that Methodist Le Bonheur is posting. The approach has the most impact on lower-acuity patients, but experts worry that in the future, payers may not be reimbursed for ED care for these patients.

  1. Effect of socioeconomic deprivation on waiting time for cardiac surgery: retrospective cohort study

    Science.gov (United States)

    Pell, Jill P; Pell, Alastair C H; Norrie, John; Ford, Ian; Cobbe, Stuart M

    2000-01-01

    Objective To determine whether the priority given to patients referred for cardiac surgery is associated with socioeconomic status. Design Retrospective study with multivariate logistic regression analysis of the association between deprivation and classification of urgency with allowance for age, sex, and type of operation. Multivariate linear regression analysis was used to determine association between deprivation and waiting time within each category of urgency, with allowance for age, sex, and type of operation. Setting NHS waiting lists in Scotland. Participants 26 642 patients waiting for cardiac surgery, 1 January 1986 to 31 December 1997. Main outcome measures Deprivation as measured by Carstairs deprivation category. Time spent on NHS waiting list. Results Patients who were most deprived tended to be younger and were more likely to be female. Patients in deprivation categories 6 and 7 (most deprived) waited about three weeks longer for surgery than those in category 1 (mean difference 24 days, 95% confidence interval 15 to 32). Deprived patients had an odds ratio of 0.5 (0.46 to 0.61) for having their operations classified as urgent compared with the least deprived, after allowance for age, sex, and type of operation. When urgent and routine cases were considered separately, there was no significant difference in waiting times between the most and least deprived categories. Conclusions Socioeconomically deprived patients are thought to be more likely to develop coronary heart disease but are less likely to be investigated and offered surgery once it has developed. Such patients may be further disadvantaged by having to wait longer for surgery because of being given lower priority. PMID:10617517

  2. Estimating the waiting time of multi-priority emergency patients with downstream blocking.

    Science.gov (United States)

    Lin, Di; Patrick, Jonathan; Labeau, Fabrice

    2014-03-01

    To characterize the coupling effect between patient flow to access the emergency department (ED) and that to access the inpatient unit (IU), we develop a model with two connected queues: one upstream queue for the patient flow to access the ED and one downstream queue for the patient flow to access the IU. Building on this patient flow model, we employ queueing theory to estimate the average waiting time across patients. Using priority specific wait time targets, we further estimate the necessary number of ED and IU resources. Finally, we investigate how an alternative way of accessing ED (Fast Track) impacts the average waiting time of patients as well as the necessary number of ED/IU resources. This model as well as the analysis on patient flow can help the designer or manager of a hospital make decisions on the allocation of ED/IU resources in a hospital.

  3. Intake of wine, beer and spirits and waiting time to pregnancy

    DEFF Research Database (Denmark)

    Juhl, Mette; Olsen, Jørn; Andersen, Anne-Marie Nybo

    2003-01-01

    BACKGROUND: A high intake of alcohol may prolong waiting time to pregnancy, whereas a moderate intake may have no or perhaps even a positive effect on fecundity. In previous studies on fecundity, different types of beverages have not been taken into consideration, although moderate wine drinkers...... appear to have fewer strokes, lung and digestive tract cancers, and overall mortality than both abstainers and moderate drinkers of beer or spirits. We examined the association between different types of alcoholic beverages and waiting time to pregnancy. METHODS: Self-reported data were used for 29......,844 pregnant women, recruited to the Danish National Birth Cohort in 1997-2000. Main outcome measures were odds ratios for a prolonged waiting time to pregnancy according to consumption of wine, beer and spirits. RESULTS: All levels of wine intake compared with non-wine drinking or with consumption of beer...

  4. Patient satisfaction with wait times at an emergency ophthalmology on-call service.

    Science.gov (United States)

    Chan, Brian J; Barbosa, Joshua; Moinul, Prima; Sivachandran, Nirojini; Donaldson, Laura; Zhao, Lily; Mullen, Sarah J; McLaughlin, Christopher R; Chaudhary, Varun

    2018-04-01

    To assess patient satisfaction with emergency ophthalmology care and determine the effect provision of anticipated appointment wait time has on scores. Single-centre, randomized control trial. Fifty patients triaged at the Hamilton Regional Eye Institute (HREI) from November 2015 to July 2016. Fifty patients triaged for next-day appointments at the HREI were randomly assigned to receive standard-of-care preappointment information or standard-of-care information in addition to an estimated appointment wait time. Patient satisfaction with care was assessed postvisit using the modified Judgements of Hospital Quality Questionnaire (JHQQ). In determining how informing patients of typical wait times influenced satisfaction, the Mann-Whitney U test was performed. As secondary study outcomes, we sought to determine patient satisfaction with the intervention material using the Fisher exact test and the effect that wait time, age, sex, education, mobility, and number of health care providers seen had on satisfaction scores using logistic regression analysis. The median JHQQ response was "very good" (4/5) and between "very good" and "excellent" (4.5/5) in the intervention and control arms, respectively. There was no difference in patient satisfaction between the cohorts (Mann-Whitney U = 297.00, p = 0.964). Logistic regression analysis demonstrated that wait times influenced patient satisfaction (OR = 0.919, 95% CI 0.864-0.978, p = 0.008). Of the intervention arm patients, 92.0% (N = 23) found the preappointment information useful, whereas only 12.5% (N = 3) of the control cohort patients noted the same (p < 0.001). Provision of anticipated wait time information to patients in an emergency on-call ophthalmology clinic did not influence satisfaction with care as captured by the JHQQ. Copyright © 2018 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

  5. Waiting for the right time: how and why young Thai women manage to avoid heterosexual intercourse.

    Science.gov (United States)

    Supametaporn, Pinhatai; Stern, Phyllis Noerager; Rodcumdee, Branom; Chaiyawat, Waraporn

    2010-08-01

    Nineteen young Thai women were purposively selected from networks of nongovernmental organizations involving children and youths in Bangkok. Our grounded theory findings indicated that these young women used the basic social process they called "waiting for the right time" in order to maintain heterosexual abstinence. Waiting for the right time involved one overarching condition, honoring parental love, and included three overlapping properties: learning rules, planning life path, and ways of preserving virginity. The findings provide information that may lead to the development of culturally competent interventions for middle-class Thai youths to remain healthy and avoid pregnancy.

  6. Waiting-time approximations in multi-queue systems with cyclic service

    NARCIS (Netherlands)

    Boxma, O.J.; Meister, B.W.

    1987-01-01

    This study is devoted to mean waiting-time approximations in a single-server multi-queue model with cyclic service and zero switching times of the server between consecutive queues. Two different service disciplines are considered: exhaustive service and (ordinary cyclic) nonexhaustive service. For

  7. Determinants of Patient Waiting Time in the General Outpatient ...

    African Journals Online (AJOL)

    The Institute of Medicine (IOM) recommends that, at least 90% of patients should be seen within 30 min of their scheduled appointment time.[5] This is, however, not the case in most developing countries, as several studies have shown that patients spend 2‑4 h in the outpatient departments before seeing the doctor.[6‑8] A ...

  8. Wait times to rheumatology care for patients with rheumatic diseases: a data linkage study of primary care electronic medical records and administrative data.

    Science.gov (United States)

    Widdifield, Jessica; Bernatsky, Sasha; Thorne, J Carter; Bombardier, Claire; Jaakkimainen, R Liisa; Wing, Laura; Paterson, J Michael; Ivers, Noah; Butt, Debra; Lyddiatt, Anne; Hofstetter, Catherine; Ahluwalia, Vandana; Tu, Karen

    2016-01-01

    The Wait Time Alliance recently established wait time benchmarks for rheumatology consultations in Canada. Our aim was to quantify wait times to primary and rheumatology care for patients with rheumatic diseases. We identified patients from primary care practices in the Electronic Medical Record Administrative data Linked Database who had referrals to Ontario rheumatologists over the period 2000-2013. To assess the full care pathway, we identified dates of symptom onset, presentation in primary care and referral from electronic medical records. Dates of rheumatologist consultations were obtained by linking with physician service claims. We determined the duration of each phase of the care pathway (symptom onset to primary care encounter, primary care encounter to referral, and referral to rheumatologist consultation) and compared them with established benchmarks. Among 2430 referrals from 168 family physicians, 2015 patients (82.9%) were seen by 146 rheumatologists within 1 year of referral. Of the 2430 referrals, 2417 (99.5%) occurred between 2005 and 2013. The main reasons for referral were osteoarthritis (32.4%) and systemic inflammatory rheumatic diseases (30.6%). Wait times varied by diagnosis and geographic region. Overall, the median wait time from referral to rheumatologist consultation was 74 (interquartile range 27-101) days; it was 66 (interquartile range 18-84) days for systemic inflammatory rheumatic diseases. Wait time benchmarks were not achieved, even for the most urgent types of referral. For systemic inflammatory rheumatic diseases, most of the delays occurred before referral. Rheumatology wait times exceeded established benchmarks. Targeted efforts are needed to promote more timely access to both primary and rheumatology care. Routine linkage of electronic medical records with administrative data may help fill important gaps in knowledge about waits to primary and specialty care.

  9. WAITING TIME DISTRIBUTION OF SOLAR ENERGETIC PARTICLE EVENTS MODELED WITH A NON-STATIONARY POISSON PROCESS

    International Nuclear Information System (INIS)

    Li, C.; Su, W.; Fang, C.; Zhong, S. J.; Wang, L.

    2014-01-01

    We present a study of the waiting time distributions (WTDs) of solar energetic particle (SEP) events observed with the spacecraft WIND and GOES. The WTDs of both solar electron events (SEEs) and solar proton events (SPEs) display a power-law tail of ∼Δt –γ . The SEEs display a broken power-law WTD. The power-law index is γ 1 = 0.99 for the short waiting times (<70 hr) and γ 2 = 1.92 for large waiting times (>100 hr). The break of the WTD of SEEs is probably due to the modulation of the corotating interaction regions. The power-law index, γ ∼ 1.82, is derived for the WTD of the SPEs which is consistent with the WTD of type II radio bursts, indicating a close relationship between the shock wave and the production of energetic protons. The WTDs of SEP events can be modeled with a non-stationary Poisson process, which was proposed to understand the waiting time statistics of solar flares. We generalize the method and find that, if the SEP event rate λ = 1/Δt varies as the time distribution of event rate f(λ) = Aλ –α exp (– βλ), the time-dependent Poisson distribution can produce a power-law tail WTD of ∼Δt α –3 , where 0 ≤ α < 2

  10. Burst wait time simulation of CALIBAN reactor at delayed super-critical state

    International Nuclear Information System (INIS)

    Humbert, P.; Authier, N.; Richard, B.; Grivot, P.; Casoli, P.

    2012-01-01

    In the past, the super prompt critical wait time probability distribution was measured on CALIBAN fast burst reactor [4]. Afterwards, these experiments were simulated with a very good agreement by solving the non-extinction probability equation [5]. Recently, the burst wait time probability distribution has been measured at CEA-Valduc on CALIBAN at different delayed super-critical states [6]. However, in the delayed super-critical case the non-extinction probability does not give access to the wait time distribution. In this case it is necessary to compute the time dependent evolution of the full neutron count number probability distribution. In this paper we present the point model deterministic method used to calculate the probability distribution of the wait time before a prescribed count level taking into account prompt neutrons and delayed neutron precursors. This method is based on the solution of the time dependent adjoint Kolmogorov master equations for the number of detections using the generating function methodology [8,9,10] and inverse discrete Fourier transforms. The obtained results are then compared to the measurements and Monte-Carlo calculations based on the algorithm presented in [7]. (authors)

  11. Burst wait time simulation of CALIBAN reactor at delayed super-critical state

    Energy Technology Data Exchange (ETDEWEB)

    Humbert, P. [Commissariat a l' Energie Atomique CEA, Centre de Bruyeres-le-Chatel, 91297 Arpajon (France); Authier, N.; Richard, B.; Grivot, P.; Casoli, P. [Commissariat a l' Energie Atomique CEA, Centre de Valduc, 21120 Is-sur-Tille (France)

    2012-07-01

    In the past, the super prompt critical wait time probability distribution was measured on CALIBAN fast burst reactor [4]. Afterwards, these experiments were simulated with a very good agreement by solving the non-extinction probability equation [5]. Recently, the burst wait time probability distribution has been measured at CEA-Valduc on CALIBAN at different delayed super-critical states [6]. However, in the delayed super-critical case the non-extinction probability does not give access to the wait time distribution. In this case it is necessary to compute the time dependent evolution of the full neutron count number probability distribution. In this paper we present the point model deterministic method used to calculate the probability distribution of the wait time before a prescribed count level taking into account prompt neutrons and delayed neutron precursors. This method is based on the solution of the time dependent adjoint Kolmogorov master equations for the number of detections using the generating function methodology [8,9,10] and inverse discrete Fourier transforms. The obtained results are then compared to the measurements and Monte-Carlo calculations based on the algorithm presented in [7]. (authors)

  12. Practical Solutions for Reducing Container Ships’ Waiting Times at Ports Using Simulation Model

    Institute of Scientific and Technical Information of China (English)

    Abdorreza Sheikholeslami; Gholamreza Ilati; Yones Eftekhari Yeganeh

    2013-01-01

    The main challenge for container ports is the planning required for berthing container ships while docked in port. Growth of containerization is creating problems for ports and container terminals as they reach their capacity limits of various resources which increasingly leads to traffic and port congestion. Good planning and management of container terminal operations reduces waiting time for liner ships. Reducing the waiting time improves the terminal’s productivity and decreases the port difficulties. Two important keys to reducing waiting time with berth allocation are determining suitable access channel depths and increasing the number of berths which in this paper are studied and analyzed as practical solutions. Simulation based analysis is the only way to understand how various resources interact with each other and how they are affected in the berthing time of ships. We used the Enterprise Dynamics software to produce simulation models due to the complexity and nature of the problems. We further present case study for berth allocation simulation of the biggest container terminal in Iran and the optimum access channel depth and the number of berths are obtained from simulation results. The results show a significant reduction in the waiting time for container ships and can be useful for major functions in operations and development of container ship terminals.

  13. Reducing waiting time and raising outpatient satisfaction in a Chinese public tertiary general hospital-an interrupted time series study

    Directory of Open Access Journals (Sweden)

    Jing Sun

    2017-08-01

    Full Text Available Abstract Background It is globally agreed that a well-designed health system deliver timely and convenient access to health services for all patients. Many interventions aiming to reduce waiting times have been implemented in Chinese public tertiary hospitals to improve patients’ satisfaction. However, few were well-documented, and the effects were rarely measured with robust methods. Methods We conducted a longitudinal study of the length of waiting times in a public tertiary hospital in Southern China which developed comprehensive data collection systems. Around an average of 60,000 outpatients and 70,000 prescribed outpatients per month were targeted for the study during Oct 2014-February 2017. We analyzed longitudinal time series data using a segmented linear regression model to assess changes in levels and trends of waiting times before and after the introduction of waiting time reduction interventions. Pearson correlation analysis was conducted to indicate the strength of association between waiting times and patient satisfactions. The statistical significance level was set at 0.05. Results The monthly average length of waiting time decreased 3.49 min (P = 0.003 for consultations and 8.70 min (P = 0.02 for filling prescriptions in the corresponding month when respective interventions were introduced. The trend shifted from baseline slight increasing to afterwards significant decreasing for filling prescriptions (P =0.003. There was a significant negative correlation between waiting time of filling prescriptions and outpatient satisfaction towards pharmacy services (r = −0.71, P = 0.004. Conclusions The interventions aimed at reducing waiting time and raising patient satisfaction in Fujian Provincial Hospital are effective. A long-lasting reduction effect on waiting time for filling prescriptions was observed because of carefully designed continuous efforts, rather than a one-time campaign, and with appropriate incentives

  14. Reducing waiting time and raising outpatient satisfaction in a Chinese public tertiary general hospital-an interrupted time series study.

    Science.gov (United States)

    Sun, Jing; Lin, Qian; Zhao, Pengyu; Zhang, Qiongyao; Xu, Kai; Chen, Huiying; Hu, Cecile Jia; Stuntz, Mark; Li, Hong; Liu, Yuanli

    2017-08-22

    It is globally agreed that a well-designed health system deliver timely and convenient access to health services for all patients. Many interventions aiming to reduce waiting times have been implemented in Chinese public tertiary hospitals to improve patients' satisfaction. However, few were well-documented, and the effects were rarely measured with robust methods. We conducted a longitudinal study of the length of waiting times in a public tertiary hospital in Southern China which developed comprehensive data collection systems. Around an average of 60,000 outpatients and 70,000 prescribed outpatients per month were targeted for the study during Oct 2014-February 2017. We analyzed longitudinal time series data using a segmented linear regression model to assess changes in levels and trends of waiting times before and after the introduction of waiting time reduction interventions. Pearson correlation analysis was conducted to indicate the strength of association between waiting times and patient satisfactions. The statistical significance level was set at 0.05. The monthly average length of waiting time decreased 3.49 min (P = 0.003) for consultations and 8.70 min (P = 0.02) for filling prescriptions in the corresponding month when respective interventions were introduced. The trend shifted from baseline slight increasing to afterwards significant decreasing for filling prescriptions (P =0.003). There was a significant negative correlation between waiting time of filling prescriptions and outpatient satisfaction towards pharmacy services (r = -0.71, P = 0.004). The interventions aimed at reducing waiting time and raising patient satisfaction in Fujian Provincial Hospital are effective. A long-lasting reduction effect on waiting time for filling prescriptions was observed because of carefully designed continuous efforts, rather than a one-time campaign, and with appropriate incentives implemented by a taskforce authorized by the hospital managers. This

  15. Access to specialist gastroenterology care in Canada: Comparison of wait times and consensus targets

    Science.gov (United States)

    Leddin, Desmond; Armstrong, David; Barkun, Alan NG; Chen, Ying; Daniels, Sandra; Hollingworth, Roger; Hunt, Richard H; Paterson, William G

    2008-01-01

    BACKGROUND: Monitoring wait times and defining targets for care have been advocated to improve health care delivery related to cancer, heart, diagnostic imaging, joint replacements and sight restoration. There are few data on access to care for digestive diseases, although they pose a greater economic burden than cancer or heart disease in Canada. The present study compared wait times for specialist gastroenterology care with recent, evidence-based, consensus-defined benchmark wait times for a range of digestive diseases. METHODS: Total wait times from primary care referral to investigation were measured for seven digestive disease indications by using the Practice Audit in Gastroenterology program, and were benchmarked against consensus recommendations. RESULTS: Total wait times for 1903 patients who were undergoing investigation exceeded targets for those with probable cancer (median 26 days [25th to 75th percentiles eight to 56 days] versus target of two weeks); probable inflammatory bowel disease (101 days [35 to 209 days] versus two weeks); documented iron deficiency anemia (71 days [19 to 142 days] versus two months); positive fecal occult blood test (73 days [36 to 148 days] versus two months); dyspepsia with alarm symptoms (60 days [23 to 140 days] versus two months); refractory dyspepsia without alarm symptoms (126 days [42 to 225 days] versus two months); and chronic constipation and diarrhea (141 days [68 to 264 days] versus two months). A minority of patients were seen within target times: probable cancer (33% [95% CI 20% to 47%]); probable inflammatory bowel disease (12% [95% CI 1% to 23%]); iron deficiency anemia (46% [95% CI 37% to 55%]); positive occult blood test (41% [95% CI 28% to 54%]); dyspepsia with alarm symptoms (51% [95% CI 41% to 60%]); refractory dyspepsia without alarm symptoms (33% [95% CI 19% to 47%]); and chronic constipation and diarrhea (21% [95% CI 14% to 29%]). DISCUSSION: Total wait times for the seven indications exceeded the

  16. Decreasing Psychiatric Admission Wait Time in the Emergency Department by Facilitating Psychiatric Discharges.

    Science.gov (United States)

    Stover, Pamela R; Harpin, Scott

    2015-12-01

    Limited capacity in a psychiatric unit contributes to long emergency department (ED) admission wait times. Regulatory and accrediting agencies urge hospitals nationally to improve patient flow for better access to care for all types of patients. The purpose of the current study was to decrease psychiatric admission wait time from 10.5 to 8 hours and increase the proportion of patients discharged by 11 a.m. from 20% to 50%. The current study compared pre- and post-intervention data. Plan-Do-Study-Act cycles aimed to improve discharge processes and timeliness through initiation of new practices. Admission wait time improved to an average of 5.1 hours (t = 3.87, p = 0.006). The proportion of discharges occurring by 11 a.m. increased to 46% (odds ratio = 3.42, p planning processes and timeliness in a psychiatric unit significantly decreased admission wait time from the ED, improving access to psychiatric care. Copyright 2015, SLACK Incorporated.

  17. A study on the impact of prioritising emergency department arrivals on the patient waiting time.

    Science.gov (United States)

    Van Bockstal, Ellen; Maenhout, Broos

    2018-05-03

    In the past decade, the crowding of the emergency department has gained considerable attention of researchers as the number of medical service providers is typically insufficient to fulfil the demand for emergency care. In this paper, we solve the stochastic emergency department workforce planning problem and consider the planning of nurses and physicians simultaneously for a real-life case study in Belgium. We study the patient arrival pattern of the emergency department in depth and consider different patient acuity classes by disaggregating the arrival pattern. We determine the personnel staffing requirements and the design of the shifts based on the patient arrival rates per acuity class such that the resource staffing cost and the weighted patient waiting time are minimised. In order to solve this multi-objective optimisation problem, we construct a Pareto set of optimal solutions via the -constraints method. For a particular staffing composition, the proposed model minimises the patient waiting time subject to upper bounds on the staffing size using the Sample Average Approximation Method. In our computational experiments, we discern the impact of prioritising the emergency department arrivals. Triaging results in lower patient waiting times for higher priority acuity classes and to a higher waiting time for the lowest priority class, which does not require immediate care. Moreover, we perform a sensitivity analysis to verify the impact of the arrival and service pattern characteristics, the prioritisation weights between different acuity classes and the incorporated shift flexibility in the model.

  18. Dynamic call center routing policies using call waiting and agent idle times

    NARCIS (Netherlands)

    Chan, W.; Koole, G.M.; L'Ecuyer, P.

    2014-01-01

    We study call routing policies for call centers with multiple call types and multiple agent groups. We introduce new weight-based routing policies where each pair (call type, agent group) is given a matching priority defined as an affine combination of the longest waiting time for that call type and

  19. Factors Associated with Waiting Time for Breast Cancer Treatment in a Teaching Hospital in Ghana

    Science.gov (United States)

    Dedey, Florence; Wu, Lily; Ayettey, Hannah; Sanuade, Olutobi A.; Akingbola, Titilola S.; Hewlett, Sandra A.; Tayo, Bamidele O.; Cole, Helen V.; de-Graft Aikins, Ama; Ogedegbe, Gbenga; Adanu, Richard

    2016-01-01

    Background: Breast cancer is the leading cause of cancer-related mortality among women in Ghana. Data are limited on the predictors of poor outcomes in breast cancer patients in low-income countries; however, prolonged waiting time has been implicated. Among breast cancer patients who received treatment at Korle Bu Teaching Hospital, this study…

  20. The unethical focus on access: a study of medical ethics and the waiting-time guarantee.

    Science.gov (United States)

    Karlberg, H I; Brinkmo, B-M

    2009-03-01

    All civilized societies favour ethical principles of equity. In healthcare, these principles generally focus on needs for medical care. Methods for establishing priorities among such needs are instrumental in this process. In this study, we analysed whether rules on access to healthcare, waiting-time guarantees, conflict with ethical principles of distributive justice. We interviewed directors, managers and other decision-makers of various healthcare providers of hospitals, primary care organizations and purchasing offices. We also conducted focus group interviews with professionals from a number of distinct medical areas. Our informants and their co-workers were reasonably familiar with the ethical platforms for priority-setting established by the Swedish parliament, giving the sickest patients complete priority. However, to satisfy the waiting-time guarantees, the informants often had to make priority decisions contrary to the ethical principles by favouring access before needs to keep waiting times within certain limits. The common opinion was that the waiting-time guarantee leads to crowding-out effects, overruling the ethical principles based on needs. For more than a decade, the interpretation in Sweden of the equitable principle based on medical needs has been distorted through political decisions, leading to healthcare providers giving priority to access rather than needs for care.

  1. Intake of wine, beer and spirits and waiting time to pregnancy.

    Science.gov (United States)

    Juhl, Mette; Olsen, Jørn; Andersen, Anne-Marie Nybo; Grønbaek, Morten

    2003-09-01

    A high intake of alcohol may prolong waiting time to pregnancy, whereas a moderate intake may have no or perhaps even a positive effect on fecundity. In previous studies on fecundity, different types of beverages have not been taken into consideration, although moderate wine drinkers appear to have fewer strokes, lung and digestive tract cancers, and overall mortality than both abstainers and moderate drinkers of beer or spirits. We examined the association between different types of alcoholic beverages and waiting time to pregnancy. Self-reported data were used for 29,844 pregnant women, recruited to the Danish National Birth Cohort in 1997-2000. Main outcome measures were odds ratios for a prolonged waiting time to pregnancy according to consumption of wine, beer and spirits. All levels of wine intake compared with non-wine drinking or with consumption of beer or spirits had subfecundity odds ratios between 0.7 and 0.9. No association was seen regarding beer drinking, while the association with spirits was J-shaped. Our findings suggest that wine drinkers have slightly shorter waiting times to pregnancy than both non-wine drinkers and consumers of other alcoholic beverages. Whether this is an effect of wine itself or the characteristics of the wine drinker is not known.

  2. Assessing and controlling the impact of hospital capacity planning on the waiting time

    NARCIS (Netherlands)

    Dellaert, N.; Çayiroglu, E.; Jeunet, J.

    2015-01-01

    In the literature, tactical plans of elective patients aim at increasing hospital efficiency through a better resource utilisation, although hospitals claim that patient satisfaction, usually measured by the waiting time, is also important. In this regard, the purpose of this paper is to show how

  3. Patients\\' response to waiting time in an out-patient pharmacy in ...

    African Journals Online (AJOL)

    Purpose: To identify the dispensing procedure at a pharmacy, investigate the possible operational problems that may lead to excessive patient waiting times as prescriptions are filled and to examine patient disposition to perceived delays at the pharmacy. Methods: The study was carried out in a 574-bed university teaching ...

  4. Modeling the impact of integrating HIV and outpatient health services on patient waiting times in an urban health clinic in Zambia.

    Directory of Open Access Journals (Sweden)

    Sarang Deo

    Full Text Available Rapid scale up of HIV treatment programs in sub-Saharan Africa has refueled the long-standing health policy debate regarding the merits and drawbacks of vertical and integrated system. Recent pilots of integrating outpatient and HIV services have shown an improvement in some patient outcomes but deterioration in waiting times, which can lead to worse health outcomes in the long run.A pilot intervention involving integration of outpatient and HIV services in an urban primary care facility in Lusaka, Zambia was studied. Data on waiting time of patients during two seven-day periods before and six months after the integration were collected using a time and motion study. Statistical tests were conducted to investigate whether the two observation periods differed in operational details such as staffing, patient arrival rates, mix of patients etc. A discrete event simulation model was constructed to facilitate a fair comparison of waiting times before and after integration. The simulation model was also used to develop alternative configurations of integration and to estimate the resulting waiting times.Comparison of raw data showed that waiting times increased by 32% and 36% after integration for OPD and ART patients respectively (p<0.01. Using simulation modeling, we found that a large portion of this increase could be explained by changes in operational conditions before and after integration such as reduced staff availability (p<0.01 and longer breaks between consecutive patients (p<0.05. Controlling for these differences, integration of services, per se, would have resulted in a significant decrease in waiting times for OPD and a moderate decrease for HIV services.Integrating health services has the potential of reducing waiting times due to more efficient use of resources. However, one needs to ensure that other operational factors such as staff availability are not adversely affected due to integration.

  5. Assessing the impact of a waiting time survey on reducing waiting times in urban primary care clinics in Cape Town, South Africa

    Directory of Open Access Journals (Sweden)

    Johann Daniels

    2017-09-01

    Full Text Available A waiting time survey (WTS conducted in several clinics in Cape Town, South Africa provided recommendations on how to shorten waiting times (WT. A follow-up study was conducted to assess whether WT had reduced. Using a stratified sample of 22 clinics, a before and after study design assessed changes in WT. The WT was measured and perceptions of clinic managers were elicited, about the previous survey’s recommendations. The overall median WT decreased by 21 minutes (95%CI: 11.77- 30.23, a 28% decrease from the previous WTS. Although no specific factor was associated with decreases in WT, implementation of recommendations to reduce WT was 2.67 times (95%CI: 1.33-5.40 more likely amongst those who received written recommendations and 2.3 times (95%CI: 1.28- 4.19 more likely amongst managers with 5 or more years’ experience. The decrease in WT found demonstrates the utility of a WTS in busy urban clinics in developing country contexts. Experienced facility managers who timeously receive customised reports of their clinic’s performance are more likely to implement changes that positively impact on reducing WT.

  6. Does Weight Gain During the Operation Wait Time Have an Impact on Weight Loss After Laparoscopic Sleeve Gastrectomy?

    Science.gov (United States)

    Cayci, Haci Murat; Erdogdu, Umut Eren; Karaman, Kerem; Budak, Ersin; Taymur, İbrahim; Buyukuysal, Cagatay

    2017-02-01

    The effect of preoperative weight changes on postoperative outcomes after bariatric surgery remains inconclusive. The aim of the present study was to evaluate the effect of preoperative weight gain on postoperative weight loss outcomes after laparoscopic sleeve gastrectomy (SG). Ninety-two morbidly obese patients undergoing SG from January 2014 to April 2016 were separated into two groups according to whether they gained weight or not during the waiting time prior to surgery. Thirty-nine patients (42.4 %) gained weight during the waiting time and 53 patients (57.6 %) did not. The median body mass index (BMI; kg/m 2 ) at surgery was significantly higher in weight-gained patients (47.8 (min-max, 40-62)) compared to patients who had not gained weight (45.10 (min-max, 41-67)), (P = 0.034). No significant difference was found between the two groups regarding the distribution of age, gender, family history of obesity, existence of comorbidity, smoking, weight gain during childhood or adulthood, preoperative Beck depression and Beck anxiety scores, waiting time period, and body weight at the initial visit (P > 0.05). The ASA I score was higher in weight-gained patients whereas ASA II score was higher in those who did not gain, and the difference was significant (P = 0.046). Postoperative % BMI loss and % weight loss were not significantly different between the two groups at the first, third, sixth months, and the end of the first year (P > 0.05). Weight gain during waiting time has no negative impact on % weight loss and % BMI loss after SG.

  7. Wait time management strategies for total joint replacement surgery: sustainability and unintended consequences.

    Science.gov (United States)

    Pomey, Marie-Pascale; Clavel, Nathalie; Amar, Claudia; Sabogale-Olarte, Juan Carlos; Sanmartin, Claudia; De Coster, Carolyn; Noseworthy, Tom

    2017-09-07

    In Canada, long waiting times for core specialized services have consistently been identified as a key barrier to access. Governments and organizations have responded with strategies for better access management, notably for total joint replacement (TJR) of the hip and knee. While wait time management strategies (WTMS) are promising, the factors which influence their sustainable implementation at the organizational level are understudied. Consequently, this study examined organizational and systemic factors that made it possible to sustain waiting times for TJR within federally established limits and for at least 18 months or more. The research design is a multiple case study of WTMS implementation. Five cases were selected across five Canadian provinces. Three success levels were pre-defined: 1) the WTMS maintained compliance with requirements for more than 18 months; 2) the WTMS met requirements for 18 months but could not sustain the level thereafter; 3) the WTMS never met requirements. For each case, we collected documents and interviewed key informants. We analyzed systemic and organizational factors, with particular attention to governance and leadership, culture, resources, methods, and tools. We found that successful organizations had specific characteristics: 1) management of the whole care continuum, 2) strong clinical leadership; 3) dedicated committees to coordinate and sustain strategy; 4) a culture based on trust and innovation. All strategies led to relatively similar unintended consequences. The main negative consequence was an initial increase in waiting times for TJR and the main positive consequence was operational enhancement of other areas of specialization based on the TJR model. This study highlights important differences in factors which help to achieve and sustain waiting times. To be sustainable, a WTMS needs to generate greater synergies between contextual-level strategy (provincial or regional) and organizational objectives and

  8. Public involvement in the priority setting activities of a wait time management initiative: a qualitative case study.

    Science.gov (United States)

    Bruni, Rebecca A; Laupacis, Andreas; Levinson, Wendy; Martin, Douglas K

    2007-11-16

    As no health system can afford to provide all possible services and treatments for the people it serves, each system must set priorities. Priority setting decision makers are increasingly involving the public in policy making. This study focuses on public engagement in a key priority setting context that plagues every health system around the world: wait list management. The purpose of this study is to describe and evaluate priority setting for the Ontario Wait Time Strategy, with special attention to public engagement. This study was conducted at the Ontario Wait Time Strategy in Ontario, Canada which is part of a Federal-Territorial-Provincial initiative to improve access and reduce wait times in five areas: cancer, cardiac, sight restoration, joint replacements, and diagnostic imaging. There were two sources of data: (1) over 25 documents (e.g. strategic planning reports, public updates), and (2) 28 one-on-one interviews with informants (e.g. OWTS participants, MOHLTC representatives, clinicians, patient advocates). Analysis used a modified thematic technique in three phases: open coding, axial coding, and evaluation. The Ontario Wait Time Strategy partially meets the four conditions of 'accountability for reasonableness'. The public was not directly involved in the priority setting activities of the Ontario Wait Time Strategy. Study participants identified both benefits (supporting the initiative, experts of the lived experience, a publicly funded system and sustainability of the healthcare system) and concerns (personal biases, lack of interest to be involved, time constraints, and level of technicality) for public involvement in the Ontario Wait Time Strategy. Additionally, the participants identified concern for the consequences (sustainability, cannibalism, and a class system) resulting from the Ontario Wait Times Strategy. We described and evaluated a wait time management initiative (the Ontario Wait Time Strategy) with special attention to public

  9. Public involvement in the priority setting activities of a wait time management initiative: a qualitative case study

    Directory of Open Access Journals (Sweden)

    Laupacis Andreas

    2007-11-01

    Full Text Available Abstract Background As no health system can afford to provide all possible services and treatments for the people it serves, each system must set priorities. Priority setting decision makers are increasingly involving the public in policy making. This study focuses on public engagement in a key priority setting context that plagues every health system around the world: wait list management. The purpose of this study is to describe and evaluate priority setting for the Ontario Wait Time Strategy, with special attention to public engagement. Methods This study was conducted at the Ontario Wait Time Strategy in Ontario, Canada which is part of a Federal-Territorial-Provincial initiative to improve access and reduce wait times in five areas: cancer, cardiac, sight restoration, joint replacements, and diagnostic imaging. There were two sources of data: (1 over 25 documents (e.g. strategic planning reports, public updates, and (2 28 one-on-one interviews with informants (e.g. OWTS participants, MOHLTC representatives, clinicians, patient advocates. Analysis used a modified thematic technique in three phases: open coding, axial coding, and evaluation. Results The Ontario Wait Time Strategy partially meets the four conditions of 'accountability for reasonableness'. The public was not directly involved in the priority setting activities of the Ontario Wait Time Strategy. Study participants identified both benefits (supporting the initiative, experts of the lived experience, a publicly funded system and sustainability of the healthcare system and concerns (personal biases, lack of interest to be involved, time constraints, and level of technicality for public involvement in the Ontario Wait Time Strategy. Additionally, the participants identified concern for the consequences (sustainability, cannibalism, and a class system resulting from the Ontario Wait Times Strategy. Conclusion We described and evaluated a wait time management initiative (the Ontario

  10. Efficiency of performing pulmonary procedures in a shared endoscopy unit: procedure time, turnaround time, delays, and procedure waiting time.

    Science.gov (United States)

    Verma, Akash; Lee, Mui Yok; Wang, Chunhong; Hussein, Nurmalah B M; Selvi, Kalai; Tee, Augustine

    2014-04-01

    The purpose of this study was to assess the efficiency of performing pulmonary procedures in the endoscopy unit in a large teaching hospital. A prospective study from May 20 to July 19, 2013, was designed. The main outcome measures were procedure delays and their reasons, duration of procedural steps starting from patient's arrival to endoscopy unit, turnaround time, total case durations, and procedure wait time. A total of 65 procedures were observed. The most common procedure was BAL (61%) followed by TBLB (31%). Overall procedures for 35 (53.8%) of 65 patients were delayed by ≥ 30 minutes, 21/35 (60%) because of "spillover" of the gastrointestinal and surgical cases into the time block of pulmonary procedure. Time elapsed between end of pulmonary procedure and start of the next procedure was ≥ 30 minutes in 8/51 (16%) of cases. In 18/51 (35%) patients there was no next case in the room after completion of the pulmonary procedure. The average idle time of the room after the end of pulmonary procedure and start of next case or end of shift at 5:00 PM if no next case was 58 ± 53 minutes. In 17/51 (33%) patients the room's idle time was >60 minutes. A total of 52.3% of patients had the wait time >2 days and 11% had it ≥ 6 days, reason in 15/21 (71%) being unavailability of the slot. Most pulmonary procedures were delayed due to spillover of the gastrointestinal and surgical cases into the block time allocated to pulmonary procedures. The most common reason for difficulty encountered in scheduling the pulmonary procedure was slot unavailability. This caused increased procedure waiting time. The strategies to reduce procedure delays and turnaround times, along with improved scheduling methods, may have a favorable impact on the volume of procedures performed in the unit thereby optimizing the existing resources.

  11. Experience of being a low priority patient during waiting time at an emergency department.

    Science.gov (United States)

    Dahlen, Ingrid; Westin, Lars; Adolfsson, Annsofie

    2012-01-01

    Work in the emergency department is characterized by fast and efficient medical efforts to save lives, but can also involve a long waiting time for patients. Patients are given a priority rating upon their arrival in the clinic based on the seriousness of their problem, and nursing care for lower priority patients is given a lower prioritization. Regardless of their medical prioritization, all patients have a right to expect good nursing care while they are waiting. The purpose of this study was to illustrate the experience of the low prioritized patient during their waiting time in the emergency department. A phenomenological hermeneutic research method was used to analyze an interview transcript. Data collection consisted of narrative interviews. The interviewees were 14 patients who had waited more than three hours for surgical, orthopedic, or other medical care. The findings resulted in four different themes, ie, being dependent on care, being exposed, being vulnerable, and being secure. Lower priority patients are not paid as much attention by nursing staff. Patients reported feeling powerless, insulted, and humiliated when their care was delayed without their understanding what was happening to them. Not understanding results in exposure that violates self-esteem. The goal of the health care provider must be to minimize and prevent suffering, prevent feelings of vulnerability, and to create conditions for optimal patient well being.

  12. Application of Queueing Theory to the Analysis of Changes in Outpatients' Waiting Times in Hospitals Introducing EMR.

    Science.gov (United States)

    Cho, Kyoung Won; Kim, Seong Min; Chae, Young Moon; Song, Yong Uk

    2017-01-01

    This research used queueing theory to analyze changes in outpatients' waiting times before and after the introduction of Electronic Medical Record (EMR) systems. We focused on the exact drawing of two fundamental parameters for queueing analysis, arrival rate (λ) and service rate (µ), from digital data to apply queueing theory to the analysis of outpatients' waiting times. We used outpatients' reception times and consultation finish times to calculate the arrival and service rates, respectively. Using queueing theory, we could calculate waiting time excluding distorted values from the digital data and distortion factors, such as arrival before the hospital open time, which occurs frequently in the initial stage of a queueing system. We analyzed changes in outpatients' waiting times before and after the introduction of EMR using the methodology proposed in this paper, and found that the outpatients' waiting time decreases after the introduction of EMR. More specifically, the outpatients' waiting times in the target public hospitals have decreased by rates in the range between 44% and 78%. It is possible to analyze waiting times while minimizing input errors and limitations influencing consultation procedures if we use digital data and apply the queueing theory. Our results verify that the introduction of EMR contributes to the improvement of patient services by decreasing outpatients' waiting time, or by increasing efficiency. It is also expected that our methodology or its expansion could contribute to the improvement of hospital service by assisting the identification and resolution of bottlenecks in the outpatient consultation process.

  13. Toward systematic reviews to understand the determinants of wait time management success to help decision-makers and managers better manage wait times.

    Science.gov (United States)

    Pomey, Marie-Pascale; Forest, Pierre-Gerlier; Sanmartin, Claudia; Decoster, Carolyn; Clavel, Nathalie; Warren, Elaine; Drew, Madeleine; Noseworthy, Tom

    2013-06-06

    Long waits for core specialized services have consistently been identified as a key barrier to access. Governments and organizations at all levels have responded with strategies for better wait list management. While these initiatives are promising, insufficient attention has been paid to factors influencing the implementation and sustainability of wait time management strategies (WTMS) implemented at the organizational level. A systematic review was conducted using the main electronic databases, such as CINAHL, MEDLINE, and Cochrane Database of Systematic Reviews, to identify articles published between 1990 and 2011 on WTMS for scheduled care implemented at the organizational level or higher and on frameworks for analyzing factors influencing their success. Data was extracted on governance, culture, resources, and tools. We organized a workshop with Canadian healthcare policy-makers and managers to compare our initial findings with their experience. Our systematic review included 47 articles: 36 related to implementation and 11 to sustainability. From these, we identified a variety of WTMS initiated at the organizational level or higher, and within these, certain factors that were specific to either implementation or sustainability and others common to both. The main common factors influencing success at the contextual level were stakeholder engagement and strong funding, and at the organizational level, physician involvement, human resources capacity, and information management systems. Specific factors for successful implementation at the contextual level were consultation with front-line actors and common standards and guidelines, and at the organizational level, financial incentives and dedicated staffing. For sustainability, we found no new factors. The workshop participants identified the same major factors as found in the articles and added others, such as information sharing between physicians and managers. Factors related to implementation were studied

  14. Experience of being a low priority patient during waiting time at an emergency department

    Directory of Open Access Journals (Sweden)

    Adolfsson A

    2012-01-01

    Full Text Available Ingrid Dahlen1,2, Lars Westin1, Annsofie Adolfsson11School of Life Sciences, University of Skövde, Skövde, Sweden; 2Emergency Department, Skaraborg Hospital, Skövde, SwedenBackground: Work in the emergency department is characterized by fast and efficient medical efforts to save lives, but can also involve a long waiting time for patients. Patients are given a priority rating upon their arrival in the clinic based on the seriousness of their problem, and nursing care for lower priority patients is given a lower prioritization. Regardless of their medical prioritization, all patients have a right to expect good nursing care while they are waiting. The purpose of this study was to illustrate the experience of the low prioritized patient during their waiting time in the emergency department.Methods: A phenomenological hermeneutic research method was used to analyze an interview transcript. Data collection consisted of narrative interviews. The interviewees were 14 patients who had waited more than three hours for surgical, orthopedic, or other medical care.Results: The findings resulted in four different themes, ie, being dependent on care, being exposed, being vulnerable, and being secure. Lower priority patients are not paid as much attention by nursing staff. Patients reported feeling powerless, insulted, and humiliated when their care was delayed without their understanding what was happening to them. Not understanding results in exposure that violates self-esteem.Conclusion: The goal of the health care provider must be to minimize and prevent suffering, prevent feelings of vulnerability, and to create conditions for optimal patient well being.Keywords: emergency department, patients, waiting times, nursing staff

  15. The British Columbia Nephrologists’ Access Study (BCNAS) – a prospective, health services interventional study to develop waiting time benchmarks and reduce wait times for out-patient nephrology consultations

    Science.gov (United States)

    2013-01-01

    Background Early referral and management of high-risk chronic kidney disease may prevent or delay the need for dialysis. Automatic eGFR reporting has increased demand for out-patient nephrology consultations and in some cases, prolonged queues. In Canada, a national task force suggested the development of waiting time targets, which has not been done for nephrology. Methods We sought to describe waiting time for outpatient nephrology consultations in British Columbia (BC). Data collection occurred in 2 phases: 1) Baseline Description (Jan 18-28, 2010) and 2) Post Waiting Time Benchmark-Introduction (Jan 16-27, 2012). Waiting time was defined as the interval from receipt of referral letters to assessment. Using a modified Delphi process, Nephrologists and Family Physicians (FP) developed waiting time targets for commonly referred conditions through meetings and surveys. Rules were developed to weigh-in nephrologists’, FPs’, and patients’ perspectives in order to generate waiting time benchmarks. Targets consider comorbidities, eGFR, BP and albuminuria. Referred conditions were assigned a priority score between 1-4. BC nephrologists were encouraged to centrally triage referrals to see the first available nephrologist. Waiting time benchmarks were simultaneously introduced to guide patient scheduling. A post-intervention waiting time evaluation was then repeated. Results In 2010 and 2012, 43/52 (83%) and 46/57 (81%) of BC nephrologists participated. Waiting time decreased from 98(IQR44,157) to 64(IQR21,120) days from 2010 to 2012 (p = management associated with improved access to nephrologists in BC. Improvements in waiting time was most marked for the highest priority patients, which suggests that benchmarks had an influence on triaging behavior. Further research is needed to determine whether this effect is sustainable. PMID:23988113

  16. Decreasing laboratory turnaround time and patient wait time by implementing process improvement methodologies in an outpatient oncology infusion unit.

    Science.gov (United States)

    Gjolaj, Lauren N; Gari, Gloria A; Olier-Pino, Angela I; Garcia, Juan D; Fernandez, Gustavo L

    2014-11-01

    Prolonged patient wait times in the outpatient oncology infusion unit indicated a need to streamline phlebotomy processes by using existing resources to decrease laboratory turnaround time and improve patient wait time. Using the DMAIC (define, measure, analyze, improve, control) method, a project to streamline phlebotomy processes within the outpatient oncology infusion unit in an academic Comprehensive Cancer Center known as the Comprehensive Treatment Unit (CTU) was completed. Laboratory turnaround time for patients who needed same-day lab and CTU services and wait time for all CTU patients was tracked for 9 weeks. During the pilot, the wait time from arrival to CTU to sitting in treatment area decreased by 17% for all patients treated in the CTU during the pilot. A total of 528 patients were seen at the CTU phlebotomy location, representing 16% of the total patients who received treatment in the CTU, with a mean turnaround time of 24 minutes compared with a baseline turnaround time of 51 minutes. Streamlining workflows and placing a phlebotomy station inside of the CTU decreased laboratory turnaround times by 53% for patients requiring same day lab and CTU services. The success of the pilot project prompted the team to make the station a permanent fixture. Copyright © 2014 by American Society of Clinical Oncology.

  17. Anomalous transport in fluid field with random waiting time depending on the preceding jump length

    International Nuclear Information System (INIS)

    Zhang Hong; Li Guo-Hua

    2016-01-01

    Anomalous (or non-Fickian) transport behaviors of particles have been widely observed in complex porous media. To capture the energy-dependent characteristics of non-Fickian transport of a particle in flow fields, in the present paper a generalized continuous time random walk model whose waiting time probability distribution depends on the preceding jump length is introduced, and the corresponding master equation in Fourier–Laplace space for the distribution of particles is derived. As examples, two generalized advection-dispersion equations for Gaussian distribution and lévy flight with the probability density function of waiting time being quadratic dependent on the preceding jump length are obtained by applying the derived master equation. (paper)

  18. Anomalous transport in fluid field with random waiting time depending on the preceding jump length

    Science.gov (United States)

    Zhang, Hong; Li, Guo-Hua

    2016-11-01

    Anomalous (or non-Fickian) transport behaviors of particles have been widely observed in complex porous media. To capture the energy-dependent characteristics of non-Fickian transport of a particle in flow fields, in the present paper a generalized continuous time random walk model whose waiting time probability distribution depends on the preceding jump length is introduced, and the corresponding master equation in Fourier-Laplace space for the distribution of particles is derived. As examples, two generalized advection-dispersion equations for Gaussian distribution and lévy flight with the probability density function of waiting time being quadratic dependent on the preceding jump length are obtained by applying the derived master equation. Project supported by the Foundation for Young Key Teachers of Chengdu University of Technology, China (Grant No. KYGG201414) and the Opening Foundation of Geomathematics Key Laboratory of Sichuan Province, China (Grant No. scsxdz2013009).

  19. Prescription duration and treatment episodes in oral glucocorticoid users: application of the parametric waiting time distribution

    DEFF Research Database (Denmark)

    Laugesen, Kristina; Støvring, Henrik; Hallas, Jesper

    2017-01-01

    for oral glucocorticoids and to describe continuous treatment episodes using the parametric waiting time distribution. Methods: We used Danish nationwide registries to identify all prescriptions for oral glucocorticoids during 1996-2014. We applied the parametric waiting time distribution to estimate...... duration of individual prescriptions each year by estimating the 80th, 90th, 95th and 99th percentiles for the interarrival distribution. These corresponded to the time since last prescription during which 80%, 90%, 95% and 99% of users presented a new prescription for redemption. We used the Kaplan...... of the interarrival distribution to apply as prescription duration has an impact on the level of misclassification. Use of the 80th percentile provides a measure of drug exposure that is specific, while the 99th percentile provides a sensitive measure....

  20. Continuous time random walk model with asymptotical probability density of waiting times via inverse Mittag-Leffler function

    Science.gov (United States)

    Liang, Yingjie; Chen, Wen

    2018-04-01

    The mean squared displacement (MSD) of the traditional ultraslow diffusion is a logarithmic function of time. Recently, the continuous time random walk model is employed to characterize this ultraslow diffusion dynamics by connecting the heavy-tailed logarithmic function and its variation as the asymptotical waiting time density. In this study we investigate the limiting waiting time density of a general ultraslow diffusion model via the inverse Mittag-Leffler function, whose special case includes the traditional logarithmic ultraslow diffusion model. The MSD of the general ultraslow diffusion model is analytically derived as an inverse Mittag-Leffler function, and is observed to increase even more slowly than that of the logarithmic function model. The occurrence of very long waiting time in the case of the inverse Mittag-Leffler function has the largest probability compared with the power law model and the logarithmic function model. The Monte Carlo simulations of one dimensional sample path of a single particle are also performed. The results show that the inverse Mittag-Leffler waiting time density is effective in depicting the general ultraslow random motion.

  1. A modelling framework for mitigating customers' waiting time at a vehicle inspection centre

    Science.gov (United States)

    Ahmad, Norazura; Abidin, Norhaslinda Zainal; Ilyas, Khibtiyah; Abduljabbar, Waleed Khalid

    2017-11-01

    In Malaysia, an agency that is entrusted by the Government to perform mandatory vehicle inspection for public, commercial and private vehicles, receive many customers daily. Often complaints of problems received from the customers are associated with waiting time that leads to lost of business and dissatisfied customers. To address this issue, we propose a framework for modelling a vehicle inspection system using an integration of simulation and optimization approaches. The strengths of simulation and optimization are reviewed briefly that is hoped to reveal the synergy between the established methods in determining an appropriate customer's waiting time for inspection at a vehicle inspection centre. Relevant concepts and preliminary results are also presented and discussed in this paper.

  2. Waiting-time distributions of magnetic discontinuities: Clustering or Poisson process?

    International Nuclear Information System (INIS)

    Greco, A.; Matthaeus, W. H.; Servidio, S.; Dmitruk, P.

    2009-01-01

    Using solar wind data from the Advanced Composition Explorer spacecraft, with the support of Hall magnetohydrodynamic simulations, the waiting-time distributions of magnetic discontinuities have been analyzed. A possible phenomenon of clusterization of these discontinuities is studied in detail. We perform a local Poisson's analysis in order to establish if these intermittent events are randomly distributed or not. Possible implications about the nature of solar wind discontinuities are discussed.

  3. Analyzing patient's waiting time in emergency & trauma department in public hospital - A case study

    Science.gov (United States)

    Roslan, Shazwa; Tahir, Herniza Md; Nordin, Noraimi Azlin Mohd; Zaharudin, Zati Aqmar

    2014-09-01

    Emergency and Trauma Department (ETD) is an important element for a hospital. It provides medical service, which operates 24 hours a day in most hospitals. However overcrowding is not exclusion for ETD. Overflowing occurs due to affordable services provided by public hospitals, since it is funded by the government. It is reported that a patient attending ETD must be treated within 90 minutes, in accordance to achieve the Key Performance Indicator (KPI). However, due to overcrowd situations, most patients have to wait longer than the KPI standard. In this paper, patient's average waiting time is analyzed. Using Chi-Square Test of Goodness, patient's inter arrival per hour is also investigated. As conclusion, Monday until Wednesday was identified as the days that exceed the KPI standard while Chi-Square Test of Goodness showed that the patient's inter arrival is independent and random.

  4. Passenger arrival and waiting time distributions dependent on train service frequency and station characteristics: A smart card data analysis

    DEFF Research Database (Denmark)

    Ingvardson, Jesper Bláfoss; Nielsen, Otto Anker; Raveau, Sebastián

    2018-01-01

    Waiting time at public transport stops is perceived by passengers to be more onerous than in-vehicle time, hence it strongly influences the attractiveness and use of public transport. Transport models traditionally assume that average waiting times are half the service headway by assuming random...... Copenhagen Area covering metro, suburban, and regional rail stations thereby giving a range of service headways from 2 to 60 min. It was shown that the proposed mixture distribution is superior to other distributions proposed in the literature. This can improve waiting time estimations in public transport...

  5. Transition in the waiting-time distribution of price-change events in a global socioeconomic system

    Science.gov (United States)

    Zhao, Guannan; McDonald, Mark; Fenn, Dan; Williams, Stacy; Johnson, Nicholas; Johnson, Neil F.

    2013-12-01

    The goal of developing a firmer theoretical understanding of inhomogeneous temporal processes-in particular, the waiting times in some collective dynamical system-is attracting significant interest among physicists. Quantifying the deviations between the waiting-time distribution and the distribution generated by a random process may help unravel the feedback mechanisms that drive the underlying dynamics. We analyze the waiting-time distributions of high-frequency foreign exchange data for the best executable bid-ask prices across all major currencies. We find that the lognormal distribution yields a good overall fit for the waiting-time distribution between currency rate changes if both short and long waiting times are included. If we restrict our study to long waiting times, each currency pair’s distribution is consistent with a power-law tail with exponent near to 3.5. However, for short waiting times, the overall distribution resembles one generated by an archetypal complex systems model in which boundedly rational agents compete for limited resources. Our findings suggest that a gradual transition arises in trading behavior between a fast regime in which traders act in a boundedly rational way and a slower one in which traders’ decisions are driven by generic feedback mechanisms across multiple timescales and hence produce similar power-law tails irrespective of currency type.

  6. A Cross-Sectional Survey of Population-Wide Wait Times for Patients Seeking Medical vs. Cosmetic Dermatologic Care.

    Directory of Open Access Journals (Sweden)

    Geeta Yadav

    Full Text Available Though previous work has examined some aspects of the dermatology workforce shortage and access to dermatologic care, little research has addressed the effect of rising interest in cosmetic procedures on access to medical dermatologic care. Our objective was to determine the wait times for Urgent and Non-Urgent medical dermatologic care and Cosmetic dermatology services at a population level and to examine whether wait times for medical care are affected by offering cosmetic services.A population-wide survey of dermatology practices using simulated calls asking for the earliest appointment for a Non-Urgent, Urgent and Cosmetic service.Response rates were greater than 89% for all types of care. Wait times across all types of care were significantly different from each other (all P < 0.05. Cosmetic care was associated with the shortest wait times (3.0 weeks; Interquartile Range (IQR = 0.4-3.4, followed by Urgent care (9.0 weeks; IQR = 2.1-12.9, then Non-Urgent Care (12.7 weeks; IQR = 4.4-16.4. Wait times for practices offering only Urgent care were not different from practices offering both Urgent and Cosmetic care (10.3 vs. 7.0 weeks.Longer wait times and greater variation for Urgent and Non-Urgent dermatologic care and shorter wait times and less variation for Cosmetic care. Wait times were significantly longer in regions with lower dermatologist density. Provision of Cosmetic services did not increase wait times for Urgent care. These findings suggest an overall dermatology workforce shortage and a need for a more streamlined referral system for dermatologic care.

  7. A Cross-Sectional Survey of Population-Wide Wait Times for Patients Seeking Medical vs. Cosmetic Dermatologic Care.

    Science.gov (United States)

    Yadav, Geeta; Goldberg, Hanna R; Barense, Morgan D; Bell, Chaim M

    2016-01-01

    Though previous work has examined some aspects of the dermatology workforce shortage and access to dermatologic care, little research has addressed the effect of rising interest in cosmetic procedures on access to medical dermatologic care. Our objective was to determine the wait times for Urgent and Non-Urgent medical dermatologic care and Cosmetic dermatology services at a population level and to examine whether wait times for medical care are affected by offering cosmetic services. A population-wide survey of dermatology practices using simulated calls asking for the earliest appointment for a Non-Urgent, Urgent and Cosmetic service. Response rates were greater than 89% for all types of care. Wait times across all types of care were significantly different from each other (all P Cosmetic care was associated with the shortest wait times (3.0 weeks; Interquartile Range (IQR) = 0.4-3.4), followed by Urgent care (9.0 weeks; IQR = 2.1-12.9), then Non-Urgent Care (12.7 weeks; IQR = 4.4-16.4). Wait times for practices offering only Urgent care were not different from practices offering both Urgent and Cosmetic care (10.3 vs. 7.0 weeks). Longer wait times and greater variation for Urgent and Non-Urgent dermatologic care and shorter wait times and less variation for Cosmetic care. Wait times were significantly longer in regions with lower dermatologist density. Provision of Cosmetic services did not increase wait times for Urgent care. These findings suggest an overall dermatology workforce shortage and a need for a more streamlined referral system for dermatologic care.

  8. Reduction of admit wait times: the effect of a leadership-based program.

    Science.gov (United States)

    Patel, Pankaj B; Combs, Mary A; Vinson, David R

    2014-03-01

    Prolonged admit wait times in the emergency department (ED) for patients who require hospitalization lead to increased boarding time in the ED, a significant cause of ED congestion. This is associated with decreased quality of care, higher morbidity and mortality, decreased patient satisfaction, increased costs for care, ambulance diversion, higher numbers of patients who leave without being seen (LWBS), and delayed care with longer lengths of stay (LOS) for other ED patients. The objective was to assess the effect of a leadership-based program to expedite hospital admissions from the ED. This before-and-after observational study was undertaken from 2006 through 2011 at one community hospital ED. A team of ED and hospital leaders implemented a program to reduce admit wait times, using a computerized hospital-wide tracking system to monitor inpatient and ED bed status. The team collaboratively and consistently moved ED patients to their inpatient beds within an established goal of 60 minutes after an admission decision was reached. Top leadership actively intervened in real time by contacting staff whenever delays occurred to expedite immediate solutions to achieve the 60-minute goal. The primary outcome measures were the percentage of ED patients who were admitted to inpatient beds within 60 minutes from the time the beds were requested and ED boarding time. LOS, patient satisfaction, LWBS rate, and ambulance diversion hours were also measured. After ED census, hospital admission rates, and ED bed capacity were controlled for using a multivariable linear regression analysis, the admit wait time reduction program contributed to an increase in patients being admitted to the hospital within 60 minutes by 16 percentage points (95% confidence intervals [CI] = 10 to 22 points; p leadership-based program to reduce admit wait times and boarding times was associated with a significant increase in the percentage of patients admitted to the hospital within 60 minutes and a

  9. Transport properties of the continuous-time random walk with a long-tailed waiting-time density

    International Nuclear Information System (INIS)

    Weissman, H.; Havlin, S.; Weiss, G.H.

    1989-01-01

    The authors derive asymptotic properties of the propagator p(r, t) of a continuous-time random walk (CTRW) in which the waiting time density has the asymptotic form ψ(t) ∼ T α /t α+1 when t >> T and 0 = ∫ 0 ∞ τψ(τ)dτ is finite. One is that the asymptotic behavior of p(0, t) is demonstrated by the waiting time at the origin rather than by the dimension. The second difference is that in the presence of a field p(r, t) no longer remains symmetric around a moving peak. Rather, it is shown that the peak of this probability always occurs at r = 0, and the effect of the field is to break the symmetry that occurs when < ∞. Finally, they calculate similar properties, although in not such great detail, for the case in which the single-step jump probabilities themselves have an infinite mean

  10. ADAPTATION OF JOHNSON SEQUENCING ALGORITHM FOR JOB SCHEDULING TO MINIMISE THE AVERAGE WAITING TIME IN CLOUD COMPUTING ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    SOUVIK PAL

    2016-09-01

    Full Text Available Cloud computing is an emerging paradigm of Internet-centric business computing where Cloud Service Providers (CSPs are providing services to the customer according to their needs. The key perception behind cloud computing is on-demand sharing of resources available in the resource pool provided by CSP, which implies new emerging business model. The resources are provisioned when jobs arrive. The job scheduling and minimization of waiting time are the challenging issue in cloud computing. When a large number of jobs are requested, they have to wait for getting allocated to the servers which in turn may increase the queue length and also waiting time. This paper includes system design for implementation which is concerned with Johnson Scheduling Algorithm that provides the optimal sequence. With that sequence, service times can be obtained. The waiting time and queue length can be reduced using queuing model with multi-server and finite capacity which improves the job scheduling model.

  11. A Study to Determine Patient Waiting Time at the Outpatient Pharmacy at Wilford Hall USAF Medical Center

    Science.gov (United States)

    1988-06-01

    at Wilford Hall USAF Medical Center significantly reduced the patient wait time at the main outpatient pharmacy. Satellite pharmacies have been ).’l...PRESENTING TO WINDOW 1, 19 MAR 88. 47 C:. A’.’E-:A: -ESCRIRTIONS PER PATIENT ...........48 H. WILFORD HALL MEDICAL CENTER OUTPATIENT QUESTIONNAIRE...that wait times at tne outpatient pharmacy were excessive. It was this concern that motivated the Medical Center Administrator to request that patient

  12. Waiting time distribution for the first conception leading to a live birth

    International Nuclear Information System (INIS)

    Shrestha, G.; Biswas, S.

    1985-01-01

    An attempt has been made in this paper to obtain probability model describing the distribution of the waiting time from marriage to first conception based on the data from marriage to first live birth. The speciality of this present approach lies in assuming the marital exposure to be finite which was assumed to be infinite by most of the earlier investigators for mathematical simplicity. Illustration of the applicability of the model on the data pertaining to first order of conception and monthly probability of conception for women married at different age groups have been illustrated in this paper. (author)

  13. Deficient neural activity subserving decision-making during reward waiting time in intertemporal choice in adult attention-deficit hyperactivity disorder.

    Science.gov (United States)

    Todokoro, Ayako; Tanaka, Saori C; Kawakubo, Yuki; Yahata, Noriaki; Ishii-Takahashi, Ayaka; Nishimura, Yukika; Kano, Yukiko; Ohtake, Fumio; Kasai, Kiyoto

    2018-04-24

    Impulsivity, which significantly affects social adaptation, is an important target behavioral characteristic in interventions for attention-deficit hyperactivity disorder (ADHD). Typically, people are willing to wait longer to acquire greater rewards. Impulsivity in ADHD may be associated with brain dysfunction in decision-making involving waiting behavior under such situations. We tested the hypothesis that brain circuitry during a period of waiting (i.e., prior to the acquisition of reward) is altered in adults with ADHD. The participants included 14 medication-free adults with ADHD and 16 healthy controls matched for age, sex, IQ, and handedness. The behavioral task had participants choose between a delayed, larger monetary reward and an immediate, smaller monetary reward, where the reward waiting time actually occurred during functional magnetic resonance imaging measurement. We tested for group differences in the contrast values of blood-oxygen-level dependent signals associated with the length of waiting time, calculated using the parametric modulation method. While the two groups did not differ in the time discounting rate, the delay-sensitive contrast values were significantly lower in the caudate and visual cortex in individuals with ADHD. The higher impulsivity scores were significantly associated with lower delay-sensitive contrast values in the caudate and visual cortex. These results suggest that deficient neural activity affects decision-making involving reward waiting time during intertemporal choice tasks, and provide an explanation for the basis of impulsivity in adult ADHD. © 2018 The Author. Psychiatry and Clinical Neurosciences © 2018 Japanese Society of Psychiatry and Neurology.

  14. Ethnographies of Waiting

    DEFF Research Database (Denmark)

    Janeja, Manpreet Kaur; Bandak, Andreas

    We all wait – in traffic jams, passport offices, school meal queues, for better weather, an end to fighting, peace. Time spent waiting produces hope, boredom, anxiety, doubt, or uncertainty. Ethnographies of Waiting explores the social phenomenon of waiting and its centrality in human society...... worth the wait?" Waiting thus conceived is intrinsic to the ethnographic method at the heart of the anthropological enterprise. Featuring detailed ethnographies from Japan, Georgia, England, Ghana, Norway, Russia and the United States, a Foreword by Craig Jeffrey and an Afterword by Ghassan Hage...

  15. A Cross-Sectional Survey of Population-Wide Wait Times for Patients Seeking Medical vs. Cosmetic Dermatologic Care

    Science.gov (United States)

    Yadav, Geeta; Goldberg, Hanna R.; Barense, Morgan D.; Bell, Chaim M.

    2016-01-01

    Background Though previous work has examined some aspects of the dermatology workforce shortage and access to dermatologic care, little research has addressed the effect of rising interest in cosmetic procedures on access to medical dermatologic care. Our objective was to determine the wait times for Urgent and Non-Urgent medical dermatologic care and Cosmetic dermatology services at a population level and to examine whether wait times for medical care are affected by offering cosmetic services. Methods A population-wide survey of dermatology practices using simulated calls asking for the earliest appointment for a Non-Urgent, Urgent and Cosmetic service. Results Response rates were greater than 89% for all types of care. Wait times across all types of care were significantly different from each other (all P dermatologic care and shorter wait times and less variation for Cosmetic care. Wait times were significantly longer in regions with lower dermatologist density. Provision of Cosmetic services did not increase wait times for Urgent care. These findings suggest an overall dermatology workforce shortage and a need for a more streamlined referral system for dermatologic care. PMID:27632206

  16. Quality management: reduction of waiting time and efficiency enhancement in an ENT-university outpatients' department

    Science.gov (United States)

    Helbig, Matthias; Helbig, Silke; Kahla-Witzsch, Heike A; May, Angelika

    2009-01-01

    Background Public health systems are confronted with constantly rising costs. Furthermore, diagnostic as well as treatment services become more and more specialized. These are the reasons for an interdisciplinary project on the one hand aiming at simplification of planning and scheduling patient appointments, on the other hand at fulfilling all requirements of efficiency and treatment quality. Methods As to understanding procedure and problem solving activities, the responsible project group strictly proceeded with four methodical steps: actual state analysis, analysis of causes, correcting measures, and examination of effectiveness. Various methods of quality management, as for instance opinion polls, data collections, and several procedures of problem identification as well as of solution proposals were applied. All activities were realized according to the requirements of the clinic's ISO 9001:2000 certified quality management system. The development of this project is described step by step from planning phase to inauguration into the daily routine of the clinic and subsequent control of effectiveness. Results Five significant problem fields could be identified. After an analysis of causes the major remedial measures were: installation of a patient telephone hotline, standardization of appointment arrangements for all patients, modification of the appointments book considering the reason for coming in planning defined working periods for certain symptoms and treatments, improvement of telephonic counselling, and transition to flexible time planning by daily updates of the appointments book. After implementation of these changes into the clinic's routine success could be demonstrated by significantly reduced waiting times and resulting increased patient satisfaction. Conclusion Systematic scrutiny of the existing organizational structures of the outpatients' department of our clinic by means of actual state analysis and analysis of causes revealed the necessity

  17. 5 CFR 531.405 - Waiting periods for within-grade increase.

    Science.gov (United States)

    2010-01-01

    ... step 4-52 calendar weeks of creditable service; (ii) Rate of basic pay equal to or greater than the... creditable service; and (iii) Rate of basic pay equal to or greater than the rate of basic pay at step 7-156... step 4-260 days of creditable service in a pay status over a period of not less than 52 calendar weeks...

  18. 78 FR 17313 - Ninety-Day Waiting Period Limitation and Technical Amendments to Certain Health Coverage...

    Science.gov (United States)

    2013-03-21

    ... health insurance issuer conditions eligibility on any employee's (part-time or full-time) having... the contracting provisions of the Federal Employee Health Benefits Program (FEHBP). OPM has... estimate that 4.1 million new employees receive group health insurance coverage through private sector...

  19. Public reporting on quality, waiting times and patient experience in 11 high-income countries.

    Science.gov (United States)

    Rechel, Bernd; McKee, Martin; Haas, Marion; Marchildon, Gregory P; Bousquet, Frederic; Blümel, Miriam; Geissler, Alexander; van Ginneken, Ewout; Ashton, Toni; Saunes, Ingrid Sperre; Anell, Anders; Quentin, Wilm; Saltman, Richard; Culler, Steven; Barnes, Andrew; Palm, Willy; Nolte, Ellen

    2016-04-01

    This article maps current approaches to public reporting on waiting times, patient experience and aggregate measures of quality and safety in 11 high-income countries (Australia, Canada, England, France, Germany, Netherlands, New Zealand, Norway, Sweden, Switzerland and the United States). Using a questionnaire-based survey of key national informants, we found that the data most commonly made available to the public are on waiting times for hospital treatment, being reported for major hospitals in seven countries. Information on patient experience at hospital level is also made available in many countries, but it is not generally available in respect of primary care services. Only one of the 11 countries (England) publishes composite measures of overall quality and safety of care that allow the ranking of providers of hospital care. Similarly, the publication of information on outcomes of individual physicians remains rare. We conclude that public reporting of aggregate measures of quality and safety, as well as of outcomes of individual physicians, remain relatively uncommon. This is likely to be due to both unresolved methodological and ethical problems and concerns that public reporting may lead to unintended consequences. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  20. Predictive event modelling in multicenter clinical trials with waiting time to response.

    Science.gov (United States)

    Anisimov, Vladimir V

    2011-01-01

    A new analytic statistical technique for predictive event modeling in ongoing multicenter clinical trials with waiting time to response is developed. It allows for the predictive mean and predictive bounds for the number of events to be constructed over time, accounting for the newly recruited patients and patients already at risk in the trial, and for different recruitment scenarios. For modeling patient recruitment, an advanced Poisson-gamma model is used, which accounts for the variation in recruitment over time, the variation in recruitment rates between different centers and the opening or closing of some centers in the future. A few models for event appearance allowing for 'recurrence', 'death' and 'lost-to-follow-up' events and using finite Markov chains in continuous time are considered. To predict the number of future events over time for an ongoing trial at some interim time, the parameters of the recruitment and event models are estimated using current data and then the predictive recruitment rates in each center are adjusted using individual data and Bayesian re-estimation. For a typical scenario (continue to recruit during some time interval, then stop recruitment and wait until a particular number of events happens), the closed-form expressions for the predictive mean and predictive bounds of the number of events at any future time point are derived under the assumptions of Markovian behavior of the event progression. The technique is efficiently applied to modeling different scenarios for some ongoing oncology trials. Case studies are considered. Copyright © 2011 John Wiley & Sons, Ltd.

  1. Gender and socioeconomic status as determinants of waiting time for inpatient surgery in a system with implicit queue management.

    Science.gov (United States)

    Arnesen, Kjell E; Erikssen, Jan; Stavem, Knut

    2002-12-01

    In a system with implicit queue management, to examine gender and socioeconomic status as determinants of waiting time for inpatient surgery, after adjusting for other potential predictors. A cohort of 452 subjects was examined in outpatient clinics of a general hospital and referred to inpatient surgery. They were followed until scheduled hospital admission (n=396) or until the requested procedure no longer was relevant (n=56). We compared waiting time between groups from referral date until hospital admission, using Kaplan-Meier estimates of waiting times and log rank test. A Cox proportional hazards model was used for assessing the risk ratio (RR) of hospital admission for scheduled surgery. Gender and socioeconomic status could not explain variations in waiting time. However, patients with suspected/verified neoplastic disease or a risk of serious deterioration without treatment had markedly shorter waiting times than the reference groups, with adjusted RR (95% confidence intervals (95%CI)) of time to receiving in-patient surgery of 2.3 (1.7-3.0) and 2.0 (1.3-3.0), respectively. Being on sick leave was associated with shorter waiting time, adjusted RR of 1.7 (1.2-2.5). Referrals from within the hospital or other hospitals had also shorter waiting times than referrals from primary health care physicians, adjusted RR=1.4 (1.1-1.8). There was no evidence of bias against women or people in lower socioeconomic classes in this implicit queue management system. However, patients' access to inpatient surgery was associated with malignancy, prognosis, sick leave status, physician experience, referral pattern and the major diagnosis category.

  2. Waiting for a pacemaker

    DEFF Research Database (Denmark)

    Risgaard, Bjarke; Elming, Hanne; Jensen, Gunnar

    2012-01-01

    AIMS: To determine waiting period-related morbidity, mortality, and adverse events in acute patients waiting for a permanent pacemaker (PPM).METHODS AND RESULTS: A retrospective chart review of all PPM implantations in Region Zealand, Denmark, in 2009 was conducted. Patients were excluded...... at least one adverse event during the waiting period. The present study indicates that a waiting period is dangerous as it is associated with an increased risk of adverse events. Acute PPMs should be implanted with a 24-h pacemaker implantation service capacity....

  3. Waiting times before dental care under general anesthesia in children with special needs in the Children's Hospital of Casablanca.

    Science.gov (United States)

    Badre, Bouchra; Serhier, Zineb; El Arabi, Samira

    2014-01-01

    Oral diseases may have an impact on quality of children's life. The presence of severe disability requires the use of care under general anesthesia (GA). However, because of the limited number of qualified health personnel, waiting time before intervention can be long. To evaluate the waiting time before dental care under general anesthesia for children with special needs in Morocco. A retrospective cohort study was carried out in pediatric dentistry unit of the University Hospital of Casablanca. Data were collected from records of patients seen for the first time between 2006 and 2011. The waiting time was defined as the time between the date of the first consultation and intervention date. 127 children received dental care under general anesthesia, 57.5% were male and the average age was 9.2 (SD = 3.4). Decay was the most frequent reason for consultation (48%), followed by pain (32%). The average waiting time was 7.6 months (SD = 4.2 months). The average number of acts performed per patient was 13.5. Waiting times were long, it is necessary to take measures to reduce delays and improve access to oral health care for this special population.

  4. Emergency Department Waiting Times (EDWaT): A Patient Flow Management and Quality of Care Rating mHealth Application.

    Science.gov (United States)

    Househ, Mowafa; Yunus, Faisel

    2014-01-01

    Saudi hospital emergency departments (ED) have suffered from long waiting times, which have led to a delay in emergency patient care. The increase in the population of Saudi Arabia is likely to further stretch the healthcare services due to overcrowding leading to decreased healthcare quality, long patient waits, patient dissatisfaction, ambulance diversions, decreased physician productivity, and increased frustration among medical staff. This will ultimately put patients at risk for poor health outcomes. Time is of the essence in emergencies and to get to an ED that has the shortest waiting time can mean life or death for a patient, especially in cases of stroke and myocardial infarction. In this paper, we present our work on the development of a mHealth Application - EDWaT - that will: provide patient flow information to the emergency medical services staff, help in quick routing of patients to the nearest hospital, and provide an opportunity for patients to review and rate the quality of care received at an ED, which will then be forwarded to ED services administrators. The quality ratings will help patients to choose between two EDs with the same waiting time and distance from their location. We anticipate that the use of EDWaT will help improve ED wait times and the quality of care provision in Saudi hospitals EDs.

  5. Wait Time Management Strategies for Scheduled Care: What Makes Them Succeed?

    Science.gov (United States)

    Pomey, Marie-Pascale; Forest, Pierre-Gerlier; Sanmartin, Claudia; De Coster, Carolyn; Drew, Madeleine

    2010-01-01

    Objectives: To assess experts' perceptions of the contextual and local factors that promote or inhibit the implementation of waiting time management strategies (WTMS) in Canadian healthcare organizations. Methods: We conducted 16 semi-structured interviews and one focus group with individuals involved in WTMS at the federal, provincial or organizational level. Results: The most frequently cited local factor was physicians' participation. Physicians' leadership made the greatest difference in bringing resistant physicians on board. To be effective, however, local leadership had to be supported by senior management. Alignment of financial incentives between the contextual and local levels was also frequently cited, and interviewees stressed the importance of tools used to design, monitor, evaluate and prioritize WTMS. Conclusions: Finding the right balance between supportive resources and tools and an effective management system is a tough challenge. But achieving this balance will help reconcile contradictions between top-down and bottom-up WTMS. PMID:21286269

  6. Lean-driven improvements slash wait times, drive up patient satisfaction scores.

    Science.gov (United States)

    2012-07-01

    Administrators at LifePoint Hospitals, based in Brentwood, TN, used lean manufacturing techniques to slash wait times by as much as 30 minutes and achieve double-digit increases in patient satisfaction scores in the EDs at three hospitals. In each case, front-line workers took the lead on identifying opportunities for improvement and redesigning the patient-flow process. As a result of the new efficiencies, patient volume is up by about 25% at all three hospitals. At each hospital, the improvement process began with Kaizen, a lean process that involves bringing personnel together to flow-chart the current system, identify problem areas, and redesign the process. Improvement teams found big opportunities for improvement at the front end of the flow process. Key to the approach was having a plan up front to deal with non-compliance. To sustain improvements, administrators gather and disseminate key metrics on a daily basis.

  7. Wait time management strategies for scheduled care: what makes them succeed?

    Science.gov (United States)

    Pomey, Marie-Pascale; Forest, Pierre-Gerlier; Sanmartin, Claudia; De Coster, Carolyn; Drew, Madeleine

    2010-02-01

    To assess experts' perceptions of the contextual and local factors that promote or inhibit the implementation of waiting time management strategies (WTMS) in Canadian healthcare organizations. We conducted 16 semi-structured interviews and one focus group with individuals involved in WTMS at the federal, provincial or organizational level. The most frequently cited local factor was physicians' participation. Physicians' leadership made the greatest difference in bringing resistant physicians on board. To be effective, however, local leadership had to be supported by senior management. Alignment of financial incentives between the contextual and local levels was also frequently cited, and interviewees stressed the importance of tools used to design, monitor, evaluate and prioritize WTMS. Finding the right balance between supportive resources and tools and an effective management system is a tough challenge. But achieving this balance will help reconcile contradictions between top-down and bottom-up WTMS.

  8. Exact and Heuristic Solutions to Minimize Total Waiting Time in the Blood Products Distribution Problem

    Directory of Open Access Journals (Sweden)

    Amir Salehipour

    2012-01-01

    Full Text Available This paper presents a novel application of operations research to support decision making in blood distribution management. The rapid and dynamic increasing demand, criticality of the product, storage, handling, and distribution requirements, and the different geographical locations of hospitals and medical centers have made blood distribution a complex and important problem. In this study, a real blood distribution problem containing 24 hospitals was tackled by the authors, and an exact approach was presented. The objective of the problem is to distribute blood and its products among hospitals and medical centers such that the total waiting time of those requiring the product is minimized. Following the exact solution, a hybrid heuristic algorithm is proposed. Computational experiments showed the optimal solutions could be obtained for medium size instances, while for larger instances the proposed hybrid heuristic is very competitive.

  9. Lung cancer care trajectory at a Canadian centre: an evaluation of how wait times affect clinical outcomes.

    Science.gov (United States)

    Kasymjanova, G; Small, D; Cohen, V; Jagoe, R T; Batist, G; Sateren, W; Ernst, P; Pepe, C; Sakr, L; Agulnik, J

    2017-10-01

    Lung cancer continues to be one of the most common cancers in Canada, with approximately 28,400 new cases diagnosed each year. Although timely care can contribute substantially to quality of life for patients, it remains unclear whether it also improves patient outcomes. In this work, we used a set of quality indicators that aim to describe the quality of care in lung cancer patients. We assessed adherence with existing guidelines for timeliness of lung cancer care and concordance with existing standards of treatment, and we examined the association between timeliness of care and lung cancer survival. Patients with lung cancer diagnosed between 2010 and 2015 were identified from the Pulmonary Division Lung Cancer Registry at our centre. We demonstrated that the interdisciplinary pulmonary oncology service successfully treated most of its patients within the recommended wait times. However, there is still work to be done to decrease variation in wait time. Our results demonstrate a significant association between wait time and survival, supporting the need for clinicians to optimize the patient care trajectory. It would be helpful for Canadian clinicians treating patients with lung cancer to have wait time guidelines for all treatment modalities, together with standard definitions for all time intervals. Any reductions in wait times should be balanced against the need for thorough investigation before initiating treatment. We believe that our unique model of care leads to an acceleration of diagnostic steps. Avoiding any delay associated with referral to a medical oncologist for treatment could be an acceptable strategy with respect to reducing wait time.

  10. Arrival time pattern and waiting time distribution of patients in the emergency outpatient department of a tertiary level health care institution of North India

    Directory of Open Access Journals (Sweden)

    Yogesh Tiwari

    2014-01-01

    Full Text Available Background: Emergency Department (ED of tertiary health care institute in India is mostly overcrowded, over utilized and inappropriately staffed. The challenges of overcrowded EDs and ill-managed patient flow and admission processes result in excessively long waits for patients. Aim: The objective of the present study was to analyze the patient flow system by assessing the arrival and waiting time distribution of patients in an Emergency out Patient Department (EOPD. Materials and Methods: This short cross-sectional descriptive study was conducted in the EOPD of a Tertiary level health care Institution in North India in the month of May, 2011. The data was obtained from 591 patients, who were present in the EOPD during the month of May, 2011. The waiting time, inter arrival time between two consecutive patients were calculated in addition to the daily census data (discharge rate, admission rate and transfer out rates etc. of the emergency. Results: Arrival time pattern of patients in the EOPD was highly stochastic with the peak arrival hours to be "9.00-12.00 h" in which around 26.3% patients arrived in the EOPD. The primary waiting areas of patients included patients "under observation" (29.6%; "waiting for routine diagnostic tests" (16.4% and "waiting for discharge" (14.6%. Around 71% patients were waiting due to reasons within emergency complex. Conclusion: The patient flow of the ED could only be addressed by multifaceted, multidisciplinary and hospital wide approach.

  11. Splitting Travel Time Based on AFC Data: Estimating Walking, Waiting, Transfer, and In-Vehicle Travel Times in Metro System

    Directory of Open Access Journals (Sweden)

    Yong-Sheng Zhang

    2015-01-01

    Full Text Available The walking, waiting, transfer, and delayed in-vehicle travel times mainly contribute to route’s travel time reliability in the metro system. The automatic fare collection (AFC system provides huge amounts of smart card records which can be used to estimate all these times distributions. A new estimation model based on Bayesian inference formulation is proposed in this paper by integrating the probability measurement of the OD pair with only one effective route, in which all kinds of times follow the truncated normal distributions. Then, Markov Chain Monte Carlo method is designed to estimate all parameters endogenously. Finally, based on AFC data in Guangzhou Metro, the estimations show that all parameters can be estimated endogenously and identifiably. Meanwhile, the truncated property of the travel time is significant and the threshold tested by the surveyed data is reliable. Furthermore, the superiority of the proposed model over the existing model in estimation and forecasting accuracy is also demonstrated.

  12. Waiting time analysis for MX/G/1 priority queues with/without vacations under random order of service discipline

    Directory of Open Access Journals (Sweden)

    Norikazu Kawasaki

    2000-01-01

    Full Text Available We study MX/G/1 nonpreemptive and preemptive-resume priority queues with/without vacations under random order of service (ROS discipline within each class. By considering the conditional waiting times given the states of the system, which an arbitrary message observes upon arrival, we derive the Laplace-Stieltjes transforms of the waiting time distributions and explicitly obtain the first two moments. The relationship for the second moments under ROS and first-come first-served disciplines extends the one found previously by Takacs and Fuhrmann for non-priority single arrival queues.

  13. Prediction problem for target events based on the inter-event waiting time

    Science.gov (United States)

    Shapoval, A.

    2010-11-01

    In this paper we address the problem of forecasting the target events of a time series given the distribution ξ of time gaps between target events. Strong earthquakes and stock market crashes are the two types of such events that we are focusing on. In the series of earthquakes, as McCann et al. show [W.R. Mc Cann, S.P. Nishenko, L.R. Sykes, J. Krause, Seismic gaps and plate tectonics: seismic potential for major boundaries, Pure and Applied Geophysics 117 (1979) 1082-1147], there are well-defined gaps (called seismic gaps) between strong earthquakes. On the other hand, usually there are no regular gaps in the series of stock market crashes [M. Raberto, E. Scalas, F. Mainardi, Waiting-times and returns in high-frequency financial data: an empirical study, Physica A 314 (2002) 749-755]. For the case of seismic gaps, we analytically derive an upper bound of prediction efficiency given the coefficient of variation of the distribution ξ. For the case of stock market crashes, we develop an algorithm that predicts the next crash within a certain time interval after the previous one. We show that this algorithm outperforms random prediction. The efficiency of our algorithm sets up a lower bound of efficiency for effective prediction of stock market crashes.

  14. The effect of a positive reappraisal coping intervention and problem-solving skills training on coping strategies during waiting period of IUI treatment: An RCT

    Science.gov (United States)

    Ghasemi, Marzieh; Kordi, Masoumeh; Asgharipour, Negar; Esmaeili, Habibollah; Amirian, Maliheh

    2017-01-01

    Background: Waiting period of fertility treatment is stressful, therefore it is necessary to use effective coping strategies to cope with waiting period of intrauterine insemination (IUI) treatment. Objective: The aim of this study was comparing the effect of the positive reappraisal coping intervention (PRCI) with the problem-solving skills training (PSS) on the coping strategies of IUI waiting period, in infertile women referred to Milad Infertility Center in Mashhad. Materials and Methods: In this randomized clinical trial, 108 women were evaluated into three groups. The control group received the routine care, but in PRCI group, two training sessions were held and they were asked to review the coping thoughts cards and fill out the daily monitoring forms during the waiting period, and in PSS group problem-solving skill were taught during 3 sessions. The coping strategies were compared between three groups on the 10th day of IUI waiting period. Results: Results showed that the mean score for problem-focused were significantly different between the control (28.54±9.70), PSS (33.71±9.31), and PRCI (30.74±10.96) (p=0.025) groups. There were significant differences between the PSS group and others groups, and mean emotion-focused were significantly different between the control (32.09±11.65), PSS (29.20±9.88), and PRCI (28.74±7.96) (p=0.036) groups. There were significant differences between the PRCI and the control group (p=0.047). Conclusion: PSS was more effective to increase problem-focused coping strategies than PRCI, therefore it is recommended that this intervention should be used in infertility treatment centers. PMID:29404530

  15. The effect of a positive reappraisal coping intervention and problem-solving skills training on coping strategies during waiting period of IUI treatment: An RCT.

    Science.gov (United States)

    Ghasemi, Marzieh; Kordi, Masoumeh; Asgharipour, Negar; Esmaeili, Habibollah; Amirian, Maliheh

    2017-11-01

    Waiting period of fertility treatment is stressful, therefore it is necessary to use effective coping strategies to cope with waiting period of intrauterine insemination (IUI) treatment. The aim of this study was comparing the effect of the positive reappraisal coping intervention (PRCI) with the problem-solving skills training (PSS) on the coping strategies of IUI waiting period, in infertile women referred to Milad Infertility Center in Mashhad. In this randomized clinical trial, 108 women were evaluated into three groups. The control group received the routine care, but in PRCI group, two training sessions were held and they were asked to review the coping thoughts cards and fill out the daily monitoring forms during the waiting period, and in PSS group problem-solving skill were taught during 3 sessions. The coping strategies were compared between three groups on the 10 th day of IUI waiting period. Results showed that the mean score for problem-focused were significantly different between the control (28.54±9.70), PSS (33.71±9.31), and PRCI (30.74±10.96) (p=0.025) groups. There were significant differences between the PSS group and others groups, and mean emotion-focused were significantly different between the control (32.09±11.65), PSS (29.20±9.88), and PRCI (28.74±7.96) (p=0.036) groups. There were significant differences between the PRCI and the control group (p=0.047). PSS was more effective to increase problem-focused coping strategies than PRCI, therefore it is recommended that this intervention should be used in infertility treatment centers.

  16. The effect of a positive reappraisal coping intervention and problem-solving skills training on coping strategies during waiting period of IUI treatment: An RCT

    Directory of Open Access Journals (Sweden)

    Marzieh Ghasemi

    2017-11-01

    Full Text Available Background: Waiting period of fertility treatment is stressful, therefore it is necessary to use effective coping strategies to cope with waiting period of intrauterine insemination (IUI treatment. Objective: The aim of this study was comparing the effect of the positive reappraisal coping intervention (PRCI with the problem-solving skills training (PSS on the coping strategies of IUI waiting period, in infertile women referred to Milad Infertility Center in Mashhad. Materials and Methods: In this randomized clinical trial, 108 women were evaluated into three groups. The control group received the routine care, but in PRCI group, two training sessions were held and they were asked to review the coping thoughts cards and fill out the daily monitoring forms during the waiting period, and in PSS group problem-solving skill were taught during 3 sessions. The coping strategies were compared between three groups on the 10th day of IUI waiting period. Results: Results showed that the mean score for problem-focused were significantly different between the control (28.54±9.70, PSS (33.71±9.31, and PRCI (30.74±10.96 (p=0.025 groups. There were significant differences between the PSS group and others groups, and mean emotion-focused were significantly different between the control (32.09±11.65, PSS (29.20±9.88, and PRCI (28.74±7.96 (p=0.036 groups. There were significant differences between the PRCI and the control group (p=0.047. Conclusion: PSS was more effective to increase problem-focused coping strategies than PRCI, therefore it is recommended that this intervention should be used in infertility treatment centers.

  17. Hospital competition, GP fundholders and waiting times in the UK internal market: the case of elective surgery.

    Science.gov (United States)

    Xavier, Ana

    2003-03-01

    In this paper I model the demand for and supply of elective surgery using a modified Hotelling framework in which time, money, and distance are determinants of the demand for hospital care. Hospitals compete with each other in terms of the waiting time and consequently treat a certain number of patients. The basic model of hospital competition is then extended to incorporate the general practitioner (GP) fundholding scheme whereby the GPs are allocated a budget with which to buy care for their patients. Waiting time increases when production of care becomes more expensive, when the benefit obtained from treatment increases, when the unit cost of distance decreases, and when the importance given to time as a performance indicator decreases. The higher the money price the lower the waiting time. Finally, the money price paid by the GP fundholders is greater than that paid by the Health Authorities and greater than the hospitals marginal cost of production. As a consequence, fundholding patients pay a zero time price while non-fundholding patients experiment a positive waiting time.

  18. Cardiac EASE (Ensuring Access and Speedy Evaluation) – the impact of a single-point-of-entry multidisciplinary outpatient cardiology consultation program on wait times in Canada

    Science.gov (United States)

    Bungard, Tammy J; Smigorowsky, Marcie J; Lalonde, Lucille D; Hogan, Terry; Doliszny, Katharine M; Gebreyesus, Ghirmay; Garg, Sipi; Archer, Stephen L

    2009-01-01

    BACKGROUND: Universal access to health care is valued in Canada but increasing wait times for services (eg, cardiology consultation) raise safety questions. Observations suggest that deficiencies in the process of care contribute to wait times. Consequently, an outpatient clinic was designed for Ensuring Access and Speedy Evaluation (Cardiac EASE) in a university group practice, providing cardiac consultative services for northern Alberta. Cardiac EASE has two components: a single-point-of-entry intake service (prospective testing using physician-approved algorithms and previsit triage) and a multidisciplinary clinic (staffed by cardiologists, nurse practitioners and doctoral-trained pharmacists). OBJECTIVES: It was hypothesized that Cardiac EASE would reduce the time to initial consultation and a definitive diagnosis, and also increase the referral capacity. METHODS: The primary and secondary outcomes were time from referral to initial consultation, and time to achieve a definitive diagnosis and management plan, respectively. A conventionally managed historical control group (three-month pre-EASE period in 2003) was compared with the EASE group (2004 to 2006). The conventional referral mechanism continued concurrently with EASE. RESULTS: A comparison between pre-EASE (n=311) and EASE (n=3096) revealed no difference in the mean (± SD) age (60±16 years), sex (55% and 52% men, respectively) or reason for referral, including chest pain (31% and 40%, respectively) and arrhythmia (27% and 29%, respectively). Cardiac EASE reduced the time to initial cardiac consultation (from 71±45 days to 33±19 days) and time to a definitive diagnosis (from 120±86 days to 51±58 days) (P<0.0001). The annual number of new referrals increased from 1512 in 2002 to 2574 in 2006 due to growth in the Cardiac EASE clinic. The number of patients seen through the conventional referral mechanism and their wait times remained constant during the study period. CONCLUSIONS: Cardiac EASE reduced

  19. Spin-resolved electron waiting times in a quantum-dot spin valve

    Science.gov (United States)

    Tang, Gaomin; Xu, Fuming; Mi, Shuo; Wang, Jian

    2018-04-01

    We study the electronic waiting-time distributions (WTDs) in a noninteracting quantum-dot spin valve by varying spin polarization and the noncollinear angle between the magnetizations of the leads using the scattering matrix approach. Since the quantum-dot spin valve involves two channels (spin up and down) in both the incoming and outgoing channels, we study three different kinds of WTDs, which are two-channel WTD, spin-resolved single-channel WTD, and cross-channel WTD. We analyze the behaviors of WTDs in short times, correlated with the current behaviors for different spin polarizations and noncollinear angles. Cross-channel WTD reflects the correlation between two spin channels and can be used to characterize the spin-transfer torque process. We study the influence of the earlier detection on the subsequent detection from the perspective of cross-channel WTD, and define the influence degree quantity as the cumulative absolute difference between cross-channel WTDs and first-passage time distributions to quantitatively characterize the spin-flip process. We observe that influence degree versus spin-transfer torque for different noncollinear angles as well as different polarizations collapse into a single curve showing universal behaviors. This demonstrates that cross-channel WTDs can be a pathway to characterize spin correlation in spintronics system.

  20. Poisson-process generalization for the trading waiting-time distribution in a double-auction mechanism

    Science.gov (United States)

    Cincotti, Silvano; Ponta, Linda; Raberto, Marco; Scalas, Enrico

    2005-05-01

    In this paper, empirical analyses and computational experiments are presented on high-frequency data for a double-auction (book) market. Main objective of the paper is to generalize the order waiting time process in order to properly model such empirical evidences. The empirical study is performed on the best bid and best ask data of 7 U.S. financial markets, for 30-stock time series. In particular, statistical properties of trading waiting times have been analyzed and quality of fits is evaluated by suitable statistical tests, i.e., comparing empirical distributions with theoretical models. Starting from the statistical studies on real data, attention has been focused on the reproducibility of such results in an artificial market. The computational experiments have been performed within the Genoa Artificial Stock Market. In the market model, heterogeneous agents trade one risky asset in exchange for cash. Agents have zero intelligence and issue random limit or market orders depending on their budget constraints. The price is cleared by means of a limit order book. The order generation is modelled with a renewal process. Based on empirical trading estimation, the distribution of waiting times between two consecutive orders is modelled by a mixture of exponential processes. Results show that the empirical waiting-time distribution can be considered as a generalization of a Poisson process. Moreover, the renewal process can approximate real data and implementation on the artificial stocks market can reproduce the trading activity in a realistic way.

  1. Statistical distributions of avalanche size and waiting times in an inter-sandpile cascade model

    Science.gov (United States)

    Batac, Rene; Longjas, Anthony; Monterola, Christopher

    2012-02-01

    Sandpile-based models have successfully shed light on key features of nonlinear relaxational processes in nature, particularly the occurrence of fat-tailed magnitude distributions and exponential return times, from simple local stress redistributions. In this work, we extend the existing sandpile paradigm into an inter-sandpile cascade, wherein the avalanches emanating from a uniformly-driven sandpile (first layer) is used to trigger the next (second layer), and so on, in a successive fashion. Statistical characterizations reveal that avalanche size distributions evolve from a power-law p(S)≈S-1.3 for the first layer to gamma distributions p(S)≈Sαexp(-S/S0) for layers far away from the uniformly driven sandpile. The resulting avalanche size statistics is found to be associated with the corresponding waiting time distribution, as explained in an accompanying analytic formulation. Interestingly, both the numerical and analytic models show good agreement with actual inventories of non-uniformly driven events in nature.

  2. A simple derivation of the waiting time distributions in a non-preemptive M/M/c queue with priorities

    NARCIS (Netherlands)

    van Vianen, Lars A.; Gabor, Adriana F.; van Ommeren, Jan C.W.

    2014-01-01

    In this article we give a new derivation for the waiting time distributions in an M=M=c queue with multiple priorities and a common service rate by using elementary lattice paths counting. An advantage of the approach is that it does not require inversion of the Laplace-Stieltjes transform.

  3. A simple derivation of the waiting time distributions in a non-preemptive M/M/c queue with priorities

    NARCIS (Netherlands)

    L.A. van Vianen (Lars); A.F. Gabor (Adriana); J.C.W. van Ommeren (Jan-Kees)

    2014-01-01

    textabstractIn this article we give a new derivation for the waiting time distributions in an M/M/c queue with multiple priorities and a common service rate by using elementary lattice paths counting. An advantage of the approach is that it does not require inversion of the Laplace-Stieltjes

  4. Improving Customer Waiting Time at a DMV Center Using Discrete-Event Simulation

    Science.gov (United States)

    Arnaout, Georges M.; Bowling, Shannon

    2010-01-01

    Virginia's Department of Motor Vehicles (DMV) serves a customer base of approximately 5.6 million licensed drivers and ID card holders and 7 million registered vehicle owners. DMV has more daily face-to-face contact with Virginia's citizens than any other state agency [1]. The DMV faces a major difficulty in keeping up with the excessively large customers' arrival rate. The consequences are queues building up, stretching out to the entrance doors (and sometimes even outside) and customers complaining. While the DMV state employees are trying to serve at their fastest pace, the remarkably large queues indicate that there is a serious problem that the DMV faces in its services, which must be dealt with rapidly. Simulation is considered as one of the best tools for evaluating and improving complex systems. In this paper, we use it to model one of the DMV centers located in Norfolk, VA. The simulation model is modeled in Arena 10.0 from Rockwell systems. The data used is collected from experts of the DMV Virginia headquarter located in Richmond. The model created was verified and validated. The intent of this study is to identify key problems causing the delays at the DMV centers and suggest possible solutions to minimize the customers' waiting time. In addition, two tentative hypotheses aiming to improve the model's design are tested and validated.

  5. Portuguese Society of Cardiothoracic and Vascular Surgery/Portuguese Society of Cardiology recommendations for waiting times for cardiac surgery.

    Science.gov (United States)

    Neves, José; Pereira, Hélder; Sousa Uva, Miguel; Gavina, Cristina; Leite Moreira, Adelino; Loureiro, Maria José

    2015-11-01

    Appointed jointly by the Portuguese Society of Cardiothoracic and Vascular Surgery (SPCCTV) and the Portuguese Society of Cardiology (SPC), the Working Group on Waiting Times for Cardiac Surgery was established with the aim of developing practical recommendations for clinically acceptable waiting times for the three critical phases of the care of adults with heart disease who require surgery or other cardiological intervention: cardiology appointments; the diagnostic process; and invasive treatment. Cardiac surgery has specific characteristics that are not comparable to other surgical specialties. It is important to reduce maximum waiting times and to increase the efficacy of systems for patient monitoring and tracking. The information in this document is mainly based on available clinical information. The methodology used to establish the criteria was based on studies on the natural history of heart disease, clinical studies comparing medical treatment with intervention, retrospective and prospective analyses of patients on waiting lists, and the opinions of experts and working groups. Following the first step, represented by publication of this document, the SPCCTV and SPC, as the bodies best suited to oversee this process, are committed to working together to define operational strategies that will reconcile the clinical evidence with the actual situation and with available resources. Copyright © 2015 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  6. A prospective study on the impact of waiting times for radiotherapy ...

    African Journals Online (AJOL)

    Background: Radiotherapy plays a vital role in the management of cervical cancer. However, because of high patient load and limited resources, waiting lists are unacceptably long. This is a highly curable malignancy that often occurs in economically active, relatively young women. The impact of treatment delays on society ...

  7. Improved functional outcome after hip fracture is associated with duration of rehabilitation, but not with waiting time for rehabilitation

    DEFF Research Database (Denmark)

    Pedersen, Tonny Jaeger; Bogh, Louise Nicole Bie; Lauritsen, Jens Martin

    2017-01-01

    INTRODUCTION: The aim of this study was to explore the relationship between “waiting time to onset of municipal rehabilitation”, “length of municipal rehabilitation” and the attained level of function four months after the hip fracture. METHODS: Among a consecutive series of 156 patients, the 116...... duration of municipal rehabilitation and outcome, also at four months. No marked differences in these results were found when subgrouped by pre-fracture level of function as assessed with the Barthel-20 index. CONCLUSIONS: Waiting times from hospital discharge to initiation of municipal rehabilitation...... seems not to correlate with functional level four months after the hip fracture. In contrast, the amount of municipal rehabilitation time does correlate with a better functional level four months after the hip fracture. Furthermore, large-sample studies are warranted to clarify this relationship....

  8. Change of tumor target volume during waiting time for intensity-modulated radiotherapy (IMRT) in nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Chen Bo; Yi Junlin; Gao Li; Xu Guozhen; Huang Xiaodong; Zhang Zhong; Luo Jingwei; Li Suyan

    2007-01-01

    Objective: To determine the influence of change in tumor target volume of nasopharyngeal carcinoma (NPC) while waiting for intensity modulated radiation therapy (IMRT). Methods: From March 2005 to December 2005, 31 patients with nasopharyngeal carcinoma received IMRT as the initial treatment at the Cancer Hospital of Chinese Academic of Medical Sciences. The original simulation CT scan was acquired before IMRT planning. A second CT scan was acquired before the start of radiotherapy. Wait- ing time was defined as the duration between CT simulation and start of radiotherapy. CT-CT fusion was used to minimize the error of delineation between the first tumor target volume (GTV) and the second tumor target volume (sGTV). Tumor target volume was calculated by treatment planning system. T test was carried out to analyse the difference between GTV and sGTV. Pearson correlation and multivariate linear regression was used to analyse the influence factor of the change betweent GTV and sGTV. Results: Median waiting time was 18 days (range, 9-27 days). There were significant differences between GTV and sGTV of both primary tumor (P=0.009) and metastatic lymphoma (P=0.005 ). Both Pearson correlation and multivariate linear regression showed that the change of primary tumor target volume had significant correlation with the first tumor target volume but had no significant correlation with the waiting time, sex, age, T stage and N stage (1992 Chinese Fuzhou Staging Classification). Conclusions: Within the range of the waiting time ob- served in our study, large volume primary tumor would have had a significant increase in volume, but whether the therapeutic effect would be influenced or not would need to be proved by study of large number of cases. Patients with large volume tumor should be considered to reduce the influence of waiting time by enlarging gross target volume and clinical targe volume and by neoadjuveant chemotherapy. For avoiding the unnecessary high-dose to normal

  9. Waiting Time for Coronal Preparation and the Influence of Different Cements on Tensile Strength of Metal Posts

    Directory of Open Access Journals (Sweden)

    Ilione Kruschewsky Costa Sousa Oliveira

    2012-01-01

    Full Text Available This study aimed to assess the effect of post-cementation waiting time for core preparation of cemented cast posts and cores had on retention in the root canal, using two different luting materials. Sixty extracted human canines were sectioned 16 mm from the root apex. After cast nickel-chromium metal posts and cores were fabricated and luted with zinc phosphate (ZP cement or resin cement (RC, the specimens were divided into 3 groups (n = 10 according to the waiting time for core preparation: no preparation (control, 15 minutes, or 1 week after the core cementation. At the appropriate time, the specimens were subjected to a tensile load test (0.5 mm/min until failure. Two-way ANOVA (time versus cement and the Tukey tests (P < 0.05 showed significantly higher (P < 0.05 tensile strength values for the ZP cement groups than for the RC groups. Core preparation and post-cementation waiting time for core recontouring did not influence the retention strength. ZP was the best material for intraradicular metal post cementation.

  10. Waiting list in a public health facility in Santiago, Chile

    Directory of Open Access Journals (Sweden)

    Alejandro Letelier

    2014-07-01

    for consultation, contact of the patient, schedule of the consultation, and the medical appointment itself. Conclusion There was low level of resolution of the waiting list, with completion of only 35% of the requests for consultation. There was also evidence of incomplete administrative procedures, as well as long waiting periods for first-time consultations on patients who were seen, up to 150 days. Patients who were not seen had a mean waiting period of almost 500 days. The management model was insufficient during the period of the study. Resolution was not timely; there was no increase in human resources. There was neither standardization of processes nor effective biomedical prioritization

  11. Prototype of a Questionnaire and Quiz System for Supporting Increase of Health Awareness During Wait Time in Dispensing Pharmacy

    Science.gov (United States)

    Toda, Takeshi; Chen, Poa-Min; Ozaki, Shinya; Ideguchi, Naoko; Miyaki, Tomoko; Nanbu, Keiko; Ikeda, Keiko

    For quit-smoking clinic and its campaign, there was a need for pharmacists to investigate pediatric patient's parent consciousness to tobacco harm utilizing wait time in a pediatric dispensing pharmacy. In this research, we developed the questionnaire and quiz total system using the tablet for user interface, in which people can easily answer the questionnaire/quiz and quickly see the total results on the spot in order to enhance their consciousness to the tobacco harm. The system also provides their tobacco dependence level based on the questionnaire results and some advice for their health and dietary habits due to the tobacco dependence level. From a field trial with one hundred four examinees in the pediatric dispensing pharmacy, the user interface was useful compared to conventional questionnaire form. The system could enhance their consciousness to tobacco harm and make their beneficial use of waiting time in dispensing pharmacy. Some interesting suggestions for improvement and new services were also obtained.

  12. The impact of travel distance, travel time and waiting time on health-related quality of life of diabetes patients: An investigation in six European countries.

    Science.gov (United States)

    Konerding, Uwe; Bowen, Tom; Elkhuizen, Sylvia G; Faubel, Raquel; Forte, Paul; Karampli, Eleftheria; Mahdavi, Mahdi; Malmström, Tomi; Pavi, Elpida; Torkki, Paulus

    2017-04-01

    The effects of travel distance and travel time to the primary diabetes care provider and waiting time in the practice on health-related quality of life (HRQoL) of patients with type 2 diabetes are investigated. Survey data of 1313 persons with type 2 diabetes from six regions in England (274), Finland (163), Germany (254), Greece (165), the Netherlands (354), and Spain (103) were analyzed. Various multiple linear regression analyses with four different EQ-5D-3L indices (English, German, Dutch and Spanish index) as target variables, with travel distance, travel time, and waiting time in the practice as focal predictors and with control for study region, patient's gender, patient's age, patient's education, time since diagnosis, thoroughness of provider-patient communication were computed. Interactions of regions with the remaining five control variables and the three focal predictors were also tested. There are no interactions of regions with control variables or focal predictors. The indices decrease with increasing travel time to the provider and increasing waiting time in the provider's practice. HRQoL of patients with type 2 diabetes might be improved by decreasing travel time to the provider and waiting time in the provider's practice. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. The relationship between waiting time for radiotherapy and clinical outcomes: A systematic review of the literature

    International Nuclear Information System (INIS)

    Chen Zheng; King, Will; Pearcey, Robert; Kerba, Marc; Mackillop, William J.

    2008-01-01

    Purpose: To synthesize the direct clinical evidence relating waiting times (WTs) for radiotherapy (RT) to the outcomes of RT. Methods and materials: We did a systematic review of the literature between 1975 and 2005 to identify clinical studies describing the relationship between WTs and outcomes of RT. Only high quality (HQ) studies that had adequately controlled for confounding factors were included in the primary analysis. WTs that had originally been reported as a categorical variable were converted to a continuous variable based on the distribution of WTs in each category. Meta-analyses were done using a fixed-effect model. Results: The systematic review identified 44 relevant studies. Meta-analyses of 20 HQ studies of local control demonstrated a significant increase in the risk of local failure with increasing WT, RR localrecurrence/month = 1.14, 95% Confidence Intervals (CI): 1.09-1.21. For post-operative RT for breast cancer; RR localrecurrence/month = 1.11, 95%CI: 1.04-1.19. For post-operative RT for head and neck cancer, RR localrecurrenc/month = 1.28, 95%CI: 1.08-1.52. For definitive RT for head and neck cancer, RR localrecurrence/month = 1.15, 95%CI: 1.02-1.29. There was little evidence of any association between WTs and the risk of distant metastasis. Meta-analyses of the 6 HQ studies of breast cancer showed RR metastasis/month = 1.04, 95%CI: 0.98-1.09. Meta-analyses of 4 HQ studies of breast cancer showed no significant decrease in survival with increasing WT, RR death/month = 1.06, 95%CI: 0.97-1.16, but there was a marginally significant decrease in survival in 4 HQ studies of head and neck cancer, RR death/month = 1.16, 95%CI: 1.02-1.32. Conclusions: The risk of local recurrence increases with increasing WTs for RT. The increase in local recurrence rate may translate into decreased survival in some clinical situations. WTs for RT should be as short as reasonably achievable

  14. Time-Varying Periodicity in Intraday Volatility

    DEFF Research Database (Denmark)

    Andersen, Torben Gustav; Thyrsgaard, Martin; Todorov, Viktor

    We develop a nonparametric test for deciding whether return volatility exhibits time-varying intraday periodicity using a long time-series of high-frequency data. Our null hypothesis, commonly adopted in work on volatility modeling, is that volatility follows a stationary process combined...... with a constant time-of-day periodic component. We first construct time-of-day volatility estimates and studentize the high-frequency returns with these periodic components. If the intraday volatility periodicity is invariant over time, then the distribution of the studentized returns should be identical across...... with estimating volatility moments through their sample counterparts. Critical values are computed via easy-to-implement simulation. In an empirical application to S&P 500 index returns, we find strong evidence for variation in the intraday volatility pattern driven in part by the current level of volatility...

  15. Impact of 'Ideal Clinic' implementation on patient waiting time in primary healthcare clinics in KwaZulu-Natal Province, South Africa: A before-and-after evaluation.

    Science.gov (United States)

    Egbujie, B A; Grimwood, A; Mothibi-Wabafor, E C; Fatti, G; Tshabalala, A M E T; Allie, S; Vilakazi, G; Oyebanji, O

    2018-03-28

    Long waiting times are a major source of dissatisfaction for patients attending public healthcare facilities in South Africa (SA). The National Department of Health has identified this as one of six priority areas for improvement. Health system-strengthening (HSS) interventions to improve patient waiting time are being implemented in public health facilities across SA as part of the 'Ideal Clinic' model. The effect of these interventions on patient waiting time needs to be assessed and evidence generated for system improvement. To determine the effect of Ideal Clinic HSS intervention on patient waiting time in public health facilities in Amajuba District, KwaZulu-Natal Province, SA. We implemented 12 months of HSS activity, including facility reorganisation and patient appointment scheduling. The major outcome of interest was the total time spent by patients in a facility during a visit. This was calculated as the median time spent, obtained through a 'before-and-after' intervention survey. Univariate and multivariate factors associated with waiting time were determined. A total of 1 763 patients from nine clinics were surveyed before and after the intervention (n=860 at baseline and n=903 at follow-up). The median overall waiting time after the intervention was 122 minutes (interquartile range (IQR) 81 - 204), compared with 116 minutes (IQR 66 - 168) before (p<0.05). Individual facility results after the intervention were mixed. Two facilities recorded statistically significant reductions in patient waiting time, while three recorded significant increases (p<0.05). Patient load per nurse, type of service received and time of arrival in facilities were all independently associated with waiting time. Patients' arrival patterns, which were determined by appointment scheduling, played a significant role in the results obtained. Implementation of the Ideal Clinic model in the selected facilities led to changes in patient waiting time. Observed changes were

  16. The influence of waiting time satisfaction on customer loyalty towards multi-stage services in a full-service restaurant: evidence from India

    OpenAIRE

    MITTAL A.

    2016-01-01

    Research shows waiting time in services is an important source of service evaluation by the customer. In fact, time is one component of the total 'cost' that the customer bears and cost is a core component of the perceived cost-benefit equation that the customer uses to evaluate her or his sustained patronage of a particular service. In most services, customers consider waiting as a waste of time. However, from the customer perspective, in the case of a full-service restaurant, waiting is exp...

  17. Use of queue modelling in the analysis of elective patient treatment governed by a maximum waiting time policy

    DEFF Research Database (Denmark)

    Kozlowski, Dawid; Worthington, Dave

    2015-01-01

    chain and discrete event simulation models, to provide an insightful analysis of the public hospital performance under the policy rules. The aim of this paper is to support the enhancement of the quality of elective patient care, to be brought about by better understanding of the policy implications...... on the utilization of public hospital resources. This paper illustrates the use of a queue modelling approach in the analysis of elective patient treatment governed by the maximum waiting time policy. Drawing upon the combined strengths of analytic and simulation approaches we develop both continuous-time Markov...

  18. No More Waits and Delays: Streamlining Workflow to Decrease Patient Time of Stay for Image-guided Musculoskeletal Procedures.

    Science.gov (United States)

    Cheung, Yvonne Y; Goodman, Eric M; Osunkoya, Tomiwa O

    2016-01-01

    Long wait times limit our ability to provide the right care at the right time and are commonly products of inefficient workflow. In 2013, the demand for musculoskeletal (MSK) procedures increased beyond our department's ability to provide efficient and timely service. We initiated a quality improvement (QI) project to increase efficiency and decrease patient time of stay. Our project team included three MSK radiologists, one senior resident, one technologist, one administrative assistant/scheduler, and the lead technologist. We adopted and followed the Lean Six Sigma DMAIC (define, measure, analyze, improve, and control) approach. The team used tools such as voice of the customer (VOC), along with affinity and SIPOC (supplier, input, process, output, customer) diagrams, to understand the current process, identify our customers, and develop a project charter in the define stage. During the measure stage, the team collected data, created a detailed process map, and identified wastes with the value stream mapping technique. Within the analyze phase, a fishbone diagram helped the team to identify critical root causes for long wait times. Scatter plots revealed relationships among time variables. Team brainstorming sessions generated improvement ideas, and selected ideas were piloted via plan, do, study, act (PDSA) cycles. The control phase continued to enable the team to monitor progress using box plots and scheduled reviews. Our project successfully decreased patient time of stay. The highly structured and logical Lean Six Sigma approach was easy to follow and provided a clear course of action with positive results. (©)RSNA, 2016.

  19. The determinants of patient waiting time in the general outpatient department of Debre Markos and Felege Hiwot hospitals in Amhara regional state, North West, Ethiopia

    Directory of Open Access Journals (Sweden)

    Melesse Belayneh

    2017-01-01

    Full Text Available Background Patient waiting time is defined as the total time from registration until consultation with a doctor. Experiences of waiting in general are perceived as complex, subjective, and culturally influenced. Registration time, payment process/cash billing, recording classification/triaged time, few human resources and work process are the determinants of patient waiting time in the general outpatient departments. However, the complexity of wait time is poorly understood and has been explored only to a limited extent. The main objective of this study to assess patient waiting time and its determinants in Debre Markos and Felge Hiwot Referral hospitals of Amhara Regional State in North West, Ethiopia. Methods A hospital based comparative cross sectional study design was employed from October 20‐ November 20, 2014. The study population was patients presenting to general outpatient departments, from which 464 patients was selected using systematic random sampling technique. Quantitative Data was collected using structured questionnaire and A check list adopted from studies. Quantitative data was coded, entered, cleaned and analyzed using SPSS Software for windows version 20.0. Linear regression and bivariate logistic regression was applied to identify the determinants of each explanatory variable on outcome (patient waiting time. Finally data was interpreted by referring to the pertinent findings from the relevant literature reviewed. Ethical approval and clearance was obtained from ethical clearance committee of the Jimma University College of Public Health & Medical Sciences Result The measured waiting time in Felge Hiwot referral hospital mean waiting time was and its standard deviation 149.2±72.1 minutes whereas 94.2±58.3 minutes in debere markos referral hospital. The major causes of the long patient waiting time was large numbers of patient with a few doctors 94(40.5%,67(28.9% ,long searching of the cards 67(28.9%,73(31.5,and long

  20. Waiting Time for Start of Outpatient Cardiac Rehabilitation: Correlations of Non Compliance to Systematic Referral After Coronary Artery Bypass Surgery

    Directory of Open Access Journals (Sweden)

    Ali Soroush

    2016-04-01

    Full Text Available Objectives To assess the waiting time, number of delays, and correlations of non-commitment to the systematic referral to the outpatient cardiac rehabilitation (CR among coronary artery bypass surgery (CABG patients. Methods The cross-sectional study data were gathered through evaluations related to 1,187 CABG patients who were referred to the outpatient CR of 1 hospital in western Iran during 2010 to 2014. The instruments included were demographics and actual risk factors checklist, single item of perceived risk factors, and Beck depression inventory (BDI. Data was analyzed via chi-square test, ANOVA, Bonferroni post hoc test, and binary logistic regression analysis. Results Among 1 187 patients (830 male, 27% had delayed referral, and the number of delays decreased from 2010 (49.3% to 2014 (7.6% (P < 0.001. The mean of the waiting time to receive outpatient CR in western Iran was an estimated 59 days. This mean has been reduced from 66 days (2010 to 53 days (2014 (P < 0.001. After adjustment for all demographics, the results indicated that diabetic patients (P = 0.002 and patients with biological (P = 0.002, behavioral (P = 0.003, or psychological (P = 0.002 perceived risk factors have less commitment. In addition, a family history of cardiac increases the possibility of commitment as 2.41 times (P < 0.001. Conclusions Despite the progressive process of patients’ admittance and acceptability of the present waiting time, especially after 2014, it seems that more attention to diabetic patients and patients without a family history of cardiac, and modification of attitudes about multiple risk factors can associate the self-care with more responsibility and it may also be affective in the control of harm consequences through commitment to the systematic referral.

  1. Reduction of client waiting time using task shifting in an antiretroviral clinic at Specialist Hospital Bauchi, Nigeria

    Directory of Open Access Journals (Sweden)

    Nisser A. Umar

    2011-02-01

    Full Text Available Aiming to assess the impact of the intervention in reducing the patients’ waiting time in the clinic, two surveys were conducted before and after task shifting intervention in an anti-retroviral (ARV clinic at the Specialist Hospital, Bauchi, Nigeria in November 2008 and April 2009, respectively. Before the task shifting, six nurses from the clinic were trained on integrated management of adolescent and adult illness, as well as on the principle and guidelines for the anti-retroviral therapy, after which their schedule in the clinic was broadened to include seeing HIV patients presenting for routine refill and follow-up visits. In this study, fifty-six and sixty patients, respectively out of 186 and 202 who attended the clinic on the days of the pre- and post-intervention surveys, were randomly sampled. Data on patients’ sex, age and marital status, whether patient a first timer or follow up visitor and the time spent in the clinic on that day as well as the number and composition of staff and equipment in the clinic was collected. The difference in waiting time spent between the first group before task shifting and second group after task shifting was statistically analyzed and significance tested using unpaired t- test. There was a reduction in the average waiting time for patients attending the clinic from 6.48 h before task shifting to 4.35 h after task shifting. The difference of mean was -2.13 h, with 95% CI: -2.44:-1.82 hours and the test of significance by unpaired t-test P

  2. Analysis of bluetooth and wi-fi technology to measure wait times of personal vehicles at Arizona-Mexico ports of entry : [executive summary].

    Science.gov (United States)

    2015-11-01

    The Arizona Department of Transportation (ADOT), Office of P3 Initiatives and International : Affairs selected Lee Engineering to analyze the penetration rate of Anonymous Re-Identification : (ARID) technology to measure wait time of U.S. and Mexico ...

  3. Applying the Lean principles of the Toyota Production System to reduce wait times in the emergency department.

    Science.gov (United States)

    Ng, David; Vail, Gord; Thomas, Sophia; Schmidt, Nicki

    2010-01-01

    In recognition of patient wait times, and deteriorating patient and staff satisfaction, we set out to improve these measures in our emergency department (ED) without adding any new funding or beds. In 2005 all staff in the ED at Hôtel-Dieu Grace Hospital began a transformation, employing Toyota Lean manufacturing principles to improve ED wait times and quality of care. Lean techniques such as value-stream mapping, just-in-time delivery techniques, workplace organization, reduction of systemic wastes, use of the worker as the source of quality improvement and ongoing refinement of our process steps formed the basis of our project. Our ED has achieved major improvements in departmental flow without adding any additional ED or inpatient beds. The mean registration to physician time has decreased from 111 minutes to 78 minutes. The number of patients who left without being seen has decreased from 7.1% to 4.3%. The length of stay (LOS) for discharged patients has decreased from a mean of 3.6 to 2.8 hours, with the largest decrease seen in our patients triaged at levels 4 or 5 using the Canadian Emergency Department Triage and Acuity Scale. We noted an improvement in ED patient satisfaction scores following the implementation of Lean principles. Lean manufacturing principles can improve the flow of patients through the ED, resulting in greater patient satisfaction along with reduced time spent by the patient in the ED.

  4. Sustainability of Routine Notification and Request legislation on eye bank tissue supply and corneal transplantation wait times in Canada.

    Science.gov (United States)

    Lee, Kenneth; Boimer, Corey; Hershenfeld, Samantha; Sharpen, Linda; Slomovic, Allan R

    2011-10-01

    To assess whether provinces with Routine Notification and Request (RNR) legislation have sustained increases in corneal tissue supply and decreases in wait times for corneal transplantation surgery. Cross-sectional survey of Canadian corneal transplant (CT) surgeons and eye banks. Canadian CT surgeons and representatives from the 10 Canadian eye banks. Voluntary and anonymous surveys were distributed between July and October 2009. Eligible CT surgeons were defined as ophthalmologists who practice in Canada; currently perform Penetrating keratoplasty (PKP), Deep anterior lamellar keratoplasty (DALK), Deep lamellar endothelial keratoplasty (DLEK), Descemet stripping endothelial keratoplasty (DSEK), or Descemet membrane endothelial keratoplasty (DMEK); and have obtained tissues from a Canadian eye bank. From 2006 to 2009, for provinces with RNR legislation and where data are available, mean wait times from date of diagnosis to date of CT surgery have increased: in Ontario, from 31 ± 34 weeks to 36 ± 27 weeks; in British Columbia, from 39 ± 20 weeks to 42 ± 35 weeks; in Manitoba, from 32 ± 23 weeks to 49 ± 36 weeks. In addition, the amount of corneal tissue in RNR provinces suitable for transplant, with the exception of British Columbia, has declined between 2006 and 2008: in Ontario, 1186 tissues to 999 tissues (16% decline); in Manitoba, 92 tissues to 83 tissues (10% decline); in New Brunswick, 129 tissues to 98 tissues (24% decline). Although initially effective, RNR legislation has not sustained an increase in corneal tissue availability nor has it shortened wait times in most provinces. Incorporation of community hospitals into the RNR catchment, improved enforcement, and continued education of hospital staff regarding the RNR process may be effective in making this legislation more sustainable in the long term. Copyright © 2011 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

  5. Relational development in children with cleft lip and palate: influence of the waiting period prior to the first surgical intervention and parental psychological perceptions of the abnormality

    Directory of Open Access Journals (Sweden)

    Grollemund Bruno

    2012-06-01

    effects will be analysed, so as to serve as a reference for improving the quality of information during the waiting period, and the quality of support provided for parents and children by the healthcare team before the first surgical intervention. Trial Registration ClinicalTrials.gov Identifier: NCT00993993.

  6. Relational development in children with cleft lip and palate: influence of the waiting period prior to the first surgical intervention and parental psychological perceptions of the abnormality.

    Science.gov (United States)

    Grollemund, Bruno; Guedeney, Antoine; Vazquez, Marie-Paule; Picard, Arnaud; Soupre, Véronique; Pellerin, Philippe; Simon, Etienne; Velten, Michel; Dissaux, Caroline; Kauffmann, Isabelle; Bruant-Rodier, Catherine; Danion-Grilliat, Anne

    2012-06-08

    the quality of information during the waiting period, and the quality of support provided for parents and children by the healthcare team before the first surgical intervention. ClinicalTrials.gov Identifier: NCT00993993.

  7. Managing patients' wait time in specialist out-patient clinic using real-time data from existing queue management and ADT systems.

    Science.gov (United States)

    Ju, John Chen; Gan, Soon Ann; Tan Siew Wee, Justine; Huang Yuchi, Peter; Mei Mei, Chan; Wong Mei Mei, Sharon; Fong, Kam Weng

    2013-01-01

    In major cancer centers, heavy patients load and multiple registration stations could cause significant wait time, and can be result in patient complains. Real-time patient journey data and visual display are useful tools in hospital patient queue management. This paper demonstrates how we capture patient queue data without deploying any tracing devices; and how to convert data into useful patient journey information to understand where interventions are likely to be most effective. During our system development, remarkable effort has been spent on resolving data discrepancy and balancing between accuracy and system performances. A web-based dashboard to display real-time information and a framework for data analysis were also developed to facilitate our clinics' operation. Result shows our system could eliminate more than 95% of data capturing errors and has improved patient wait time data accuracy since it was deployed.

  8. Patient perceptions regarding physician reimbursements, wait times, and out-of-pocket payments for anterior cruciate ligament reconstruction in Ontario.

    Science.gov (United States)

    Memon, Muzammil; Ginsberg, Lydia; de Sa, Darren; Nashed, Andrew; Simunovic, Nicole; Phillips, Mark; Denkers, Matthew; Ogilvie, Rick; Peterson, Devin; Ayeni, Olufemi R

    2017-12-01

    Currently, there is a lack of knowledge regarding patient perceptions surrounding physician reimbursements, appropriate wait times, and out-of-pocket payment options for anterior cruciate ligament reconstruction (ACLR). Our objective was to determine the current state of these perceptions in an Ontario setting. A survey was developed and pretested to address patient perceptions about physician reimbursements, appropriate wait times, and out-of-pocket payment options for ACLR using a focus group of experts and by reviewing prior surveys. The survey was administered to patients in a waiting room setting. Two hundred and fifty completed surveys were obtained (79.9% response rate). Participants responded that an appropriate physician reimbursement for ACLR was $1000.00 and that the Ontario Health Insurance Plan (OHIP) reimbursed physicians $700.00 for ACLR. Seventy-four percent of participants responded that the OHIP reimbursement of $615.20 for the procedure was either lower or much lower than what they considered to be an appropriate reimbursement for ACLR. Over 90% of participants responded that an ACLR should occur within 90 days of injury. Thirty-five percent of participants were willing to pay $750.00 out-of-pocket to have an ACLR done sooner, while 16.4% of participants were willing to pay $2500.00 out-of-pocket to travel outside of Canada for expedited surgery. This survey study demonstrates that patients' estimates of both appropriate and actual physician reimbursements were greater than the current reimbursement for ACLR. Further, the majority of individuals report that the surgical fee for ACLR is lower than what they consider to be an appropriate amount of compensation for the procedure. Additionally, nearly all respondents believe that a ruptured ACL should be reconstructed within 90 days of injury. Consequently, a number of patients are willing to pay out-of-pocket for expedited surgery either in Canada or abroad. However, patients' preferences for

  9. Forecasting with periodic autoregressive time series models

    NARCIS (Netherlands)

    Ph.H.B.F. Franses (Philip Hans); R. Paap (Richard)

    1999-01-01

    textabstractThis paper is concerned with forecasting univariate seasonal time series data using periodic autoregressive models. We show how one should account for unit roots and deterministic terms when generating out-of-sample forecasts. We illustrate the models for various quarterly UK consumption

  10. Using lean manufacturing principles to evaluate wait times for HIV-positive patients in an urban clinic in Kenya.

    Science.gov (United States)

    Monroe-Wise, Aliza; Reisner, Elizabeth; Sherr, Kenneth; Ojakaa, David; Mbau, Lilian; Kisia, Paul; Muhula, Samuel; Farquhar, Carey

    2017-12-01

    As human immunodeficiency virus (HIV) treatment programs expand in Africa, delivery systems must be strengthened to support patient retention. Clinic characteristics may affect retention, but a relationship between clinic flow and attrition is not established. This project characterized HIV patient experience and flow in an urban Kenyan clinic to understand how these may affect retention. We used Toyota's lean manufacturing principles to guide data collection and analysis. Clinic flow was evaluated using value stream mapping and time and motion techniques. Clinic register data were analyzed. Two focus group discussions were held to characterize HIV patient experience. Results were shared with clinic staff. Wait times in the clinic were highly variable. We identified four main barriers to patient flow: inconsistent patient arrivals, inconsistent staffing, filing system defects, and serving patients out of order. Focus group participants explained how clinic operations affected their ability to engage in care. Clinic staff were eager to discuss the problems identified and identified numerous low-cost potential solutions. Lean manufacturing methodologies can guide efficiency interventions in low-resource healthcare settings. Using lean techniques, we identified bottlenecks to clinic flow and low-cost solutions to improve wait times. Improving flow may result in increased patient satisfaction and retention.

  11. THE INFLUENCE OF WAITING TIME SATISFACTION ON CUSTOMER LOYALTY TOWARDS MULTI-STAGE SERVICES IN A FULL-SERVICE RESTAURANT: EVIDENCE FROM INDIA

    Directory of Open Access Journals (Sweden)

    A. Mittal

    2016-06-01

    Full Text Available Research shows waiting time in services is an important source of service evaluation by the customer. In fact, time is one component of the total 'cost' that the customer bears and cost is a core component of the perceived cost-benefit equation that the customer uses to evaluate her or his sustained patronage of a particular service. In most services, customers consider waiting as a waste of time. However, from the customer perspective, in the case of a full-service restaurant, waiting is expected and sometimes desirable also. Prior research, mainly in the west, suggests that when customers think that a wait for service is too long, they become less satisfied with overall service quality. Based on a research setting in a full-scale restaurant in India, this paper seeks answers to two research questions: First, what are the determinants of overall waiting-time satisfaction and second, what is the influence of waiting-time satisfaction on customer loyalty.

  12. A "package solution" fast track program can reduce the diagnostic waiting time in head and neck cancer

    DEFF Research Database (Denmark)

    Sørensen, Jesper Roed; Johansen, Jørgen; Gano, Lars

    2014-01-01

    and Neck Surgery during three comparable time intervals 2006-2007, 2007-2008, and 2011-2012 (groups 1-3) were investigated. We recorded the time from patient referral, to first consultation and final diagnosis. The first interval was before initiation of the "package solution", the second just after......In 2007, a fast track program for patients with suspicion of head and neck cancer (HNC) was introduced in Denmark to reduce unnecessary waiting time. The program was based on so called "package solutions" including pre-booked slots for outpatient evaluation, imaging, and diagnostic surgical...... procedures. The purpose of this study is to present a model for fast track handling of patients suspicious of cancer in the head and neck region and to evaluate the effect of implementation on the diagnostic work up time. Patients with suspicion of HNC referred to the same university department of ENT Head...

  13. The effectiveness of service delivery initiatives at improving patients' waiting times in clinical radiology departments: a systematic review.

    Science.gov (United States)

    Olisemeke, B; Chen, Y F; Hemming, K; Girling, A

    2014-12-01

    We reviewed the literature for the impact of service delivery initiatives (SDIs) on patients' waiting times within radiology departments. We searched MEDLINE, EMBASE, CINAHL, INSPEC and The Cochrane Library for relevant articles published between 1995 and February, 2013. The Cochrane EPOC risk of bias tool was used to assess the risk of bias on studies that met specified design criteria. Fifty-seven studies met the inclusion criteria. The types of SDI implemented included extended scope practice (ESP, three studies), quality management (12 studies), productivity-enhancing technologies (PETs, 29 studies), multiple interventions (11 studies), outsourcing and pay-for-performance (one study each). The uncontrolled pre- and post-intervention and the post-intervention designs were used in 54 (95%) of the studies. The reporting quality was poor: many of the studies did not test and/or report the statistical significance of their results. The studies were highly heterogeneous, therefore meta-analysis was inappropriate. The following type of SDIs showed promising results: extended scope practice; quality management methodologies including Six Sigma, Lean methodology, and continuous quality improvement; productivity-enhancing technologies including speech recognition reporting, teleradiology and computerised physician order entry systems. We have suggested improved study design and the mapping of the definitions of patient waiting times in radiology to generic timelines as a starting point for moving towards a situation where it becomes less restrictive to compare and/or pool the results of future studies in a meta-analysis.

  14. Appointment waiting times and education level influence the quality of bowel preparation in adult patients undergoing colonoscopy

    Directory of Open Access Journals (Sweden)

    Goh Khean-Lee

    2011-07-01

    Full Text Available Abstract Background Risk factors for poor bowel preparation are recognized to be independent of the type of bowel preparation method used. Patient and administrative factors influencing bowel preparation are known to vary in different healthcare systems. Methods A prospective, cross-sectional study of patients undergoing colonoscopy in an Asian tertiary centre was conducted to identify risk factors associated with poor bowel preparation, and to evaluate the impact of poor bowel preparation on technical performance and patient comfort. Results Data on 501 patients (mean age 60.1 ± 14.0 years old, 51.2% males, 60.9% with secondary education or higher was available for analysis. Poor bowel preparation was present in 151 patients (30.1%. Lower education level (OR = 2.35, 95% CI = 1.54 - 3.60, colonoscopy appointment waiting time beyond 16 weeks (OR = 1.86, 95% CI = 1.04 - 3.37 and non-adherence to bowel preparation instructions (OR = 4.76, 95% CI = 3.00 - 7.55 were identified as independent risk factors for poor bowel preparation. Poor bowel preparation was associated with a lower cecal intubation rate (78.1% versus 98.3%, p Conclusions Education levels and appointment waiting times, in addition to non-adherence to bowel preparation instructions, increase the risk of poor bowel preparation in adult patients undergoing colonoscopy. The latter has a significant impact on colonoscopy performance and patient comfort.

  15. Whole body magnetic resonance in indolent lymphomas under watchful waiting. The time is now

    Energy Technology Data Exchange (ETDEWEB)

    Galia, Massimo; Albano, Domenico; Midiri, Massimo; Lagalla, Roberto [University of Palermo, Department of Radiology, Di.Bi.Med., Palermo (Italy); Tarella, Corrado [European Institute of Oncology, Hemato-Oncology Division, Milan (Italy); Patti, Caterina; Mule, Antonino [Azienda Ospedaliera Ospedali Riuniti Villa Sofia-Cervello, Department of Hematology I, Palermo (Italy); Sconfienza, Luca Maria [IRCCS Istituto Ortopedico Galeazzi, Unit of Diagnostic and Interventional Radiology, Milano (Italy); Universita degli Studi di Milano, Department of Biomedical Sciences for Health, Milano (Italy); Alongi, Pierpaolo [Fondazione Istituto G. Giglio, Contrada Pietrapollastra-Pisciotto, Department of Radiological Sciences, Nuclear Medicine Unit, Cefalu (Italy)

    2018-03-15

    The indolent non-Hodgkin lymphomas (i-NHLs) are characterised by 'indolent' clinical behaviour with slow growth and prolonged natural history. The watchful waiting (WW) strategy is a frequently employed treatment option in these patients. This implies a strict monitoring by imaging examinations, including 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG-PET/CT) and CT. A major concern is radiation exposure due to regularly monitoring by conventional imaging procedures. Several studies have demonstrated the reliability of whole-body magnetic resonance imaging (WB-MRI) for lymphoma staging. WB-MRI could be useful for active surveillance in i-NHLs providing the suspect of disease progression that can be then confirmed by additional diagnostic procedures, including 18F-FDG-PET/CT. The directive 2013/59 by the European Union claims that if a radiation-free imaging technique allows obtaining the same diagnostic results, it should be invariably used. In this setting, WB-MRI may be considered a reasonable option in i-NHLs under WW, replacing imaging modalities that cause exposure to ionising radiations. This will help to reduce the cancer risk in i-NHL patients for whom chemo-/radiotherapy remain the usual treatment options following the usually long WW phase. The scientific community should raise the awareness of the risk of ionising radiations in i-NHLs and the emphasise the need for establishing the proper place of WB-MRI in lymphoma imaging. (orig.)

  16. Estimating medication stopping fraction and real-time prevalence of drug use in pharmaco-epidemiologic databases. An application of the reverse waiting time distribution

    DEFF Research Database (Denmark)

    Støvring, Henrik; Pottegård, Anton; Hallas, Jesper

    2017-01-01

    Purpose: To introduce the reverse waiting time distribution (WTD) and show how it can be used to estimate stopping fractions and real-time prevalence of treatment in pharmacoepidemiological studies. Methods: The reverse WTD is the distribution of time from the last dispensed prescription of each......-hoc decision rules for automated implementations, and it yields estimates of real-time prevalence....... patient within a time window to the end of it. It is a mirrored version of the ordinary WTD, which considers the first dispensed prescription of patients within a time window. Based on renewal process theory, the reverse WTD can be analyzed as an ordinary WTD with maximum likelihood estimation. Based...

  17. [Surgery for colorectal cancer since the introduction of the Netherlands national screening programmeInvestigations into changes in number of resections and waiting times for surgery].

    Science.gov (United States)

    de Neree Tot Babberich, M P M; van der Willik, E M; van Groningen, J T; Ledeboer, M; Wiggers, T; Wouters, M W J M

    2017-01-01

    To investigate the impact of the Netherlands national colorectal cancer screening programme on the number of surgical resections for colorectal carcinoma and on waiting times for surgery. Descriptive study. Data were extracted from the Dutch Surgical Colorectal Audit. Patients with primary colorectal cancer surgery between 2011-2015 were included. The volume and median waiting times for the years 2011-2015 are described. Waiting times from first tumor positive biopsy until the operation (biopsy-operation) and first preoperative visit to the surgeon until the operation (visit-operation) are analyzed with a univariate and multivariate linear regression analysis. Separate analysis was done for visit-operation for academic and non-academic hospitals and for screening compared to non-screening patients. In 2014 there was an increase of 1469 (15%) patients compared to 2013. In 2015 this increase consisted of 1168 (11%) patients compared to 2014. In 2014 and 2015, 1359 (12%) and 3111 (26%) patients were referred to the surgeon through screening, respectively. The median waiting time of biopsy-operation significantly decreased (ß: 0.94, 95%BI) over the years 2014-2015 compared to 2011-2013. In non-academic hospitals, the waiting time visit-operation also decreased significantly (ß: 0.89, 95%BI 0.87-0.90) over the years 2014-2015 compared to 2011-2013. No difference was found in waiting times between patients referred to the surgeon through screening compared to non-screening. There is a clear increase in volume since the introduction of the colorectal cancer screening programme without an increase in waiting time until surgery.

  18. The influence of deterministic and stochastic waiting time for triggering mortality and colonization events on the coexistence of cooperators and defectors in an evolutionary game model

    Directory of Open Access Journals (Sweden)

    YouHua Chen

    2014-06-01

    Full Text Available In the present report, the coexistence of Prisoners' Dilemma game players (cooperators and defectors were explored in an individual-based framework with the consideration of the impacts of deterministic and stochastic waiting time (WT for triggering mortality and/or colonization events. For the type of deterministic waiting time, the time step for triggering a mortality and/or colonization event is fixed. For the type of stochastic waiting time, whether a mortality and/or colonization event should be triggered for each time step of a simulation is randomly determined by a given acceptance probability (the event takes place when a variate drawn from a uniform distribution [0,1] is smaller than the acceptance probability. The two strategies of modeling waiting time are considered simultaneously and applied to both quantities (mortality: WTm, colonization: WTc. As such, when WT (WTm and/or WTc is an integral >=1, it indicated a deterministically triggering strategy. In contrast, when 1>WT>0, it indicated a stochastically triggering strategy and the WT value itself is used as the acceptance probability. The parameter space between the waiting time for mortality (WTm-[0.1,40] and colonization (WTc-[0.1,40] was traversed to explore the coexistence and non-coexistence regions. The role of defense award was evaluated. My results showed that, one non-coexistence region is identified consistently, located at the area where 1>=WTm>=0.3 and 40>=WTc>=0.1. As a consequence, it was found that the coexistence of cooperators and defectors in the community is largely dependent on the waiting time of mortality events, regardless of the defense or cooperation rewards. When the mortality events happen in terms of stochastic waiting time (1>=WTm>=0.3, extinction of either cooperators or defectors or both could be very likely, leading to the emergence of non-coexistence scenarios. However, when the mortality events occur in forms of relatively long deterministic

  19. Evaluating wait times from screening to breast cancer diagnosis among women undergoing organised assessment vs usual care.

    Science.gov (United States)

    Chiarelli, Anna M; Muradali, Derek; Blackmore, Kristina M; Smith, Courtney R; Mirea, Lucia; Majpruz, Vicky; O'Malley, Frances P; Quan, May Lynn; Holloway, Claire Mb

    2017-05-09

    Timely coordinated diagnostic assessment following an abnormal screening mammogram reduces patient anxiety and may optimise breast cancer prognosis. Since 1998, the Ontario Breast Screening Program (OBSP) has offered organised assessment through Breast Assessment Centres (BACs). For OBSP women seen at a BAC, an abnormal mammogram is followed by coordinated referrals through the use of navigators for further imaging, biopsy, and surgical consultation as indicated. For OBSP women seen through usual care (UC), further diagnostic imaging is arranged directly from the screening centre and/or through their physician; results must be communicated to the physician who is then responsible for arranging any necessary biopsy and/or surgical consultation. This study aims to evaluate factors associated with diagnostic wait times for women undergoing assessment through BAC and UC. Of the 2 147 257 women aged 50-69 years screened in the OBSP between 1 January 2002 and 31 December 2009, 155 866 (7.3%) had an abnormal mammogram. A retrospective design identified two concurrent cohorts of women diagnosed with screen-detected breast cancer at a BAC (n=4217; 47%) and UC (n=4827; 53%). Multivariable logistic regression analyses examined associations between wait times and assessment and prognostic characteristics by pathway. A two-sided 5% significance level was used. Screened women with breast cancer were two times more likely to be diagnosed within 7 weeks when assessed through a BAC vs UC (OR=1.91, 95% CI=1.73-2.10). In addition, compared with UC, women assessed through a BAC were significantly more likely to have their first assessment procedure within 3 weeks of their abnormal mammogram (OR=1.25, 95% CI=1.12-1.39), ⩽3 assessment procedures (OR=1.54, 95% CI=1.41-1.69), ⩽2 assessment visits (OR=1.86, 95% CI=1.70-2.05), and ⩾2 procedures per visit (OR=1.41, 95% CI=1.28-1.55). Women diagnosed through a BAC were also more likely than those in UC to have imaging (OR=1.99, 95

  20. Patients' perceptions of waiting for bariatric surgery: a qualitative study.

    Science.gov (United States)

    Gregory, Deborah M; Temple Newhook, Julia; Twells, Laurie K

    2013-10-18

    In Canada waiting lists for bariatric surgery are common, with wait times on average > 5 years. The meaning of waiting for bariatric surgery from the patients' perspective must be understood if health care providers are to act as facilitators in promoting satisfaction with care and quality care outcomes. The aims of this study were to explore patients' perceptions of waiting for bariatric surgery, the meaning and experience of waiting, the psychosocial and behavioral impact of waiting for treatment and identify health care provider and health system supportive measures that could potentially improve the waiting experience. Twenty-one women and six men engaged in in-depth interviews that were digitally recorded, transcribed verbatim and analysed using a grounded theory approach to data collection and analysis between June 2011 and April 2012. The data were subjected to re-analysis to identify perceived health care provider and health system barriers to accessing bariatric surgery. Thematic analysis identified inequity as a barrier to accessing bariatric surgery. Three areas of perceived inequity were identified from participants' accounts: socioeconomic inequity, regional inequity, and inequity related to waitlist prioritization. Although excited about their acceptance as candidates for surgery, the waiting period was described as stressful, anxiety provoking, and frustrating. Anger was expressed towards the health care system for the long waiting times. Participants identified the importance of health care provider and health system supports during the waiting period. Recommendations on how to improve the waiting experience included periodic updates from the surgeon's office about their position on the wait list; a counselor who specializes in helping people going through this surgery, dietitian support and further information on what to expect after surgery, among others. Patients' perceptions of accessing and waiting for bariatric surgery are shaped by perceived

  1. Waiting experience in railway environments

    NARCIS (Netherlands)

    van Hagen, M.; Galetzka, Mirjam; Pruyn, Adriaan T.H.

    2014-01-01

    At railway stations, waiting time is usually an unavoidable aspect of the journey for train passengers. According to the attentional model of time, pleasant surroundings and other forms of distraction reduce perceived waiting time. Not every individual reacts identically in the same surroundings.

  2. Improvement in Obstructive Sleep Apnea Diagnosis and Management Wait Times: A Retrospective Analysis of a Home Management Pathway for Obstructive Sleep Apnea

    Directory of Open Access Journals (Sweden)

    Samuel Alan Stewart

    2015-01-01

    Full Text Available Obstructive sleep apnea is a common condition within the Canadian population. The current gold standard for diagnosis and management of patients is in-laboratory (in-lab polysomnography; however, the limited availability of testing options for patients has led to long wait times and increased disease burden within the population. The Sleep Research Laboratory in Saskatoon (Saskatchewan implemented a home management program to run in parallel with the in-lab system several years ago in an effort to increase their capacity and reduce wait times. The present study was a retrospective analysis of all patients referred to the program between 2009 and 2012. The home management system has improved wait times by diagnosing and managing up to one-half of the referred patient population, reducing the wait for in-lab treatment from a median of 152 days in 2009 to 92 days in 2012 (P<0.0001. Moving forward, home management can provide a viable alternative to in-lab testing for patients who meet strict entry criteria, reducing the in-lab workload and, ultimately, reducing wait times.

  3. The effects of feeding frequency on waiting time, milking frequency, cubicle and feeding fence utilization for cows in an automatic milking system

    NARCIS (Netherlands)

    Oostra, H.H.; Stefanowska, J.; Sallvik, K.

    2005-01-01

    In this trial, the effects of the forage feeding frequency on the waiting time prior to milking and the cowshed facility utilization by cows milked in an automatic milking unit (AMU) were studied. The feeding frequency was increased from two times per day to six times per day. It was found that the

  4. 77 FR 56210 - Granting of Request for Early Termination of the Waiting Period Under the Premerger Notification...

    Science.gov (United States)

    2012-09-12

    ...; Volker Straub; Wells Fargo & Company. 20121180 G Apple Inc.; AuthenTec, Inc.; Apple Inc. 20121204 G..., 2012 Through August 31, 2012 08/01/2012 20120945 G Technip S.A.; The Shaw Group Inc.; Technip S.A... Energy Corporation; DTE Energy Company. 08/03/2012 20121098 G Time Warner Inc.; Bleacher Report, Inc...

  5. Comparison of The Effects of A Positive Reappraisal Coping Intervention and Problem-Solving Skills Training on Depression during The Waiting Period of The Result of Intrauterine Insemination Treatment: A Randomized Control Trial.

    Science.gov (United States)

    Ghasemi Gojani, Marzieh; Kordi, Masoumeh; Asgharipour, Negar; Esmaeili, Habibollah

    2018-04-01

    The outcomes of fertility treatments are unpredictable, and levels of depressive symptoms increase in patients during the waiting period of the result of intrauterine insemination (IUI) treatment. The aim of this study was to compare the effects of a positive reappraisal coping intervention (PRCI) and problem-solving skills training (PSS) on depression during the waiting period of the result of IUI Treatment. This randomized control clinical trial was done among 108 women undergoing IUI treatment. In the control group, the women received routine care. In the PRCI group, women attended two training sessions and were asked to complete coping thoughts cards and fill out daily monitoring forms during the waiting period. In the PSS group, PSS were taught over three sessions. The depression was measured by the beck depression inventory. On the 10 th th day of the IUI waiting period, there were significant differences between the control group (21.42 ± 11.42) and the PSS group (12.52 ± 8.05) and PRCI groups (13.14 ± 9.7) (P<0.001), but no significant difference between the PRCI group and the PSS group. According to the results of this randomized control trial there is no difference between a PRCI and PSS on depression during the waiting period of the result of IUI treatment. This suggests that both interventions can be used to help infertile women combat depression during the waiting period of the result of fertility treatments (Registration number: IRCT2016020926490N1). Copyright© by Royan Institute. All rights reserved.

  6. Comparison of The Effects of A Positive Reappraisal Coping Intervention and Problem-Solving Skills Training on Depression during The Waiting Period of The Result of Intrauterine Insemination Treatment: A Randomized Control Trial

    Directory of Open Access Journals (Sweden)

    Marzieh Ghasemi gojani, , ,

    2018-01-01

    Full Text Available Background The outcomes of fertility treatments are unpredictable, and levels of depressive symptoms increase in patients during the waiting period of the result of intrauterine insemination (IUI treatment. The aim of this study was to compare the effects of a positive reappraisal coping intervention (PRCI and problem-solving skills training (PSS on depression during the waiting period of the result of IUI Treatment. Materials and Methods This randomized control clinical trial was done among 108 women undergoing IUI treat- ment. In the control group, the women received routine care. In the PRCI group, women attended two training sessions and were asked to complete coping thoughts cards and fill out daily monitoring forms during the waiting period. In the PSS group, PSS were taught over three sessions. The depression was measured by the beck depression inventory. Results On the 10th day of the IUI waiting period, there were significant differences between the control group (21.42 ± 11.42 and the PSS group (12.52 ± 8.05 and PRCI groups (13.14 ± 9.7 (P<0.001, but no significant difference between the PRCI group and the PSS group. Conclusion According to the results of this randomized control trial there is no difference between a PRCI and PSS on depression during the waiting period of the result of IUI treatment. This suggests that both interventions can be used to help infertile women combat depression during the waiting period of the result of fertility treatments (Registration number: IRCT2016020926490N1.

  7. Polling Systems with Two-Phase Gated Service: Heavy Traffic Results for the Waiting Time Distribution

    NARCIS (Netherlands)

    R.D. van der Mei (Rob); J.A.C. Resing

    2008-01-01

    htmlabstractWe study an asymmetric cyclic polling system with Poisson arrivals, general service-time and switch-over time distributions, and with so-called two-phase gated service at each queue, an interleaving scheme that aims to enforce some level of "fairness" among the different customer

  8. A probabilistic model for estimating the waiting time until the simultaneous collapse of two contingencies

    International Nuclear Information System (INIS)

    Barnett, C.S.

    1991-01-01

    The Double Contingency Principle (DCP) is widely applied to criticality safety practice in the United States. Most practitioners base their application of the principle on qualitative, intuitive assessments. The recent trend toward probabilistic safety assessments provides a motive to search for a quantitative, probabilistic foundation for the DCP. A Markov model is tractable and leads to relatively simple results. The model yields estimates of mean time to simultaneous collapse of two contingencies as a function of estimates of mean failure times and mean recovery times of two independent contingencies. The model is a tool that can be used to supplement the qualitative methods now used to assess effectiveness of the DCP. (Author)

  9. Commercial border crossing and wait time measurement at the Pharr-Reynosa International Bridge.

    Science.gov (United States)

    2010-11-01

    The objective of the research described in this report is to install and implement radio frequency : identification (RFID) technology to measure border crossing time and travel delay for : commercial trucks crossing from Mexico into Texas at the Phar...

  10. An explicit solution for a renewal process with waiting time and its variational principle

    International Nuclear Information System (INIS)

    Lewins, J.D.

    2001-01-01

    The forward and backward equations for the conditional probability density are derived for a reliability system consisting of a single component whose repair is subject to a delay time in providing a spare part but whose mean rate of repair is otherwise constant and whose time to failure is exponentially distributed. Exact solutions are quoted. These equations are then shown to be an adjoint pair that provide stationary conditions for a variational principle, in elementary form, from which all properties of the systems can be predicted with an accuracy greater than that implied by the trial functions or approximations used. A second or specific form of variational principle provides specific estimates to questions at hand. The second or adjoint field in the first elementary principle is the backward Kolmogorov solution and the in the specific form is the importance function, as used in nuclear reactor theory. The solutions are given for long-time and in a recurrence relation form valid for all times so that approximate solutions can be checked. Approximations suitable for variational trial functions are given. Two examples give the effect of a change of delay time for a steady state and an initial transient, respectively

  11. A probabilistic model for estimating the waiting time until the simultaneous collapse of two contingencies

    International Nuclear Information System (INIS)

    Barnett, C.S.

    1991-06-01

    The Double Contingency Principle (DCP) is widely applied to criticality safety practice in the United States. Most practitioners base their application of the principle on qualitative, intuitive assessments. The recent trend toward probabilistic safety assessments provides a motive to search for a quantitative, probabilistic foundation for the DCP. A Markov model is tractable and leads to relatively simple results. The model yields estimates of mean time to simultaneous collapse of two contingencies as a function of estimates of mean failure times and mean recovery times of two independent contingencies. The model is a tool that can be used to supplement the qualitative methods now used to assess effectiveness of the DCP. 3 refs., 1 fig

  12. A probabilistic model for estimating the waiting time until the simultaneous collapse of two contingencies

    International Nuclear Information System (INIS)

    Barnett, C.S.

    1992-01-01

    The double contingency principle (DCP) is widely applied to criticality safety practice in the United States. Most practitioners base their application of the principle on qualitative and intuitive assessments. The recent trend toward probabilistic safety assessments provides a motive for a search for a quantitative and probabilistic foundation for the DCP. A Markov model is tractable and leads to relatively simple results. The model yields estimates of mean time to simultaneous collapse of two contingencies, as functions of estimates of mean failure times and mean recovery times of two independent contingencies. The model is a tool that can be used to supplement the qualitative methods now used to assess the effectiveness of the DCP. (Author)

  13. The customer waiting time in an (R,s,Q) inventory system

    NARCIS (Netherlands)

    Kiesmüller, G.P.; Kok, de A.G.

    2006-01-01

    In practice of inventory management customer-oriented service measures play an important role. If inventory managers of stockpoints in a supply chain promise specific times of delivery that cannot be met due to a lack of stock, leadtimes at downstream stockpoints increase, causing substantial

  14. Real-Time Wait-Free Queues using Micro-Transactions

    OpenAIRE

    Meawad, Fadi; Iyer, Karthik; Schoeberl, Martin; Vitek, Jan

    2011-01-01

    This paper evaluates the applicability of transactional mem- ory to the implementation of dierent non-blocking data structures in the context of the Real-time Specication for Java. In particular, we argue that hardware support for micro-transaction allows us to implement eciently data structures that are often dicult to realize with the atomic operations provided by stock hardware. Our main imple- mentation platform is the Java Optimized Processor sys- tem. We report on the performance of dat...

  15. Waiting for the Unicorn: Perception of Time and History in Early Chinese Writings

    OpenAIRE

    Gibas, Piotr Pawel

    2009-01-01

    In this dissertation I examine temporality as conceived in early Chinese historiography, through a systematic examination of four key works: the Mozi, the Zuozhuan, the Rishu;, and the Chu Silk Manuscript, all of them written during 4th through 1st century BCE. Each presents from a different perspective ideas about the mechanism of time and history. While only the Zuozhuan is commonly categorized as historical narrative, all four of these texts depend on records of the past to convey their wo...

  16. Real-Time Wait-Free Queues using Micro-Transactions

    DEFF Research Database (Denmark)

    Meawad, Fadi; Iyer, Karthik; Schoeberl, Martin

    2011-01-01

    This paper evaluates the applicability of transactional mem- ory to the implementation of dierent non-blocking data structures in the context of the Real-time Specication for Java. In particular, we argue that hardware support for micro-transaction allows us to implement eciently data structures...... that are often dicult to realize with the atomic operations provided by stock hardware. Our main imple- mentation platform is the Java Optimized Processor sys- tem. We report on the performance of data structures imple- mented with locks, compare and swap and micro-transactions. Our results conrm...

  17. Waiting time to radiotherapy as a prognostic factor for glioblastoma patients in a scenario of medical disparities

    Energy Technology Data Exchange (ETDEWEB)

    Loureiro, Luiz Victor Maia; Callegaro-Filho, Donato; Koch, Ludmila de Oliveira; Weltman, Eduardo; Victor, Elivane da Silva; Malheiros, Suzana Maria Fleury, E-mail: lvmaia@gmail.com [Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil); Santos, Adrialdo Jose; Borges, Lia Raquel Rodrigues; Segreto, Roberto Araujo [Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, SP (Brazil). Escola paulista de Medicina; Pontes, Luciola de Barros [Hospital do Coracao, Sao Paulo, SP (Brazil). Dept. de Oncologia

    2015-02-15

    Objective: to evaluate the effect of waiting time (WT) to radiotherapy (RT) on overall survival (OS) of glioblastoma (GBM) patients as a reliable prognostic variable in Brazil, a scenario of medical disparities. Method: retrospective study of 115 GBM patients from two different health-care institutions (one public and one private) in Brazil who underwent post-operative RT. Results: Median WT to RT was 6 weeks (range,1.3-17.6). The median OS for WT ≤ 6 weeks was 13.5 months (95%CI , 9.1-17.9) and for WT . 6 weeks was 14.2 months (95%CI, 11.2-17.2) (HR 1.165, 95%CI 0.770-1.762; p = 0.470). In the multivariate analysis, the variables associated with survival were KPS (p , 0.001), extent of resection (p = 0.009) and the adjuvant treatment (p = 0.001). The KPS interacted with WT to RT (HR 0.128, 95%CI 0.034-0.476; p = 0.002), showing that the benefit of KPS on OS depends on the WT to RT. Conclusion: no prognostic impact of WT to RT could be detected on the OS. Although there are no data to ensure that delays to RT are tolerable, we may reassure patients that the time-length to initiate treatment does not seem to influence the control of the disease, particularly in face of other prognostic factors. (author)

  18. Using business process redesign to reduce wait times at a university hospital in the Netherlands.

    Science.gov (United States)

    Elkhuizen, Sylvia G; Burger, Matthe P M; Jonkers, Rene E; Limburg, Martien; Klazinga, Niek; Bakker, Piet J M

    2007-06-01

    Business process redesign (BPR) has been applied to implement more customer-focused and cost-effective care. In 2002, two pilot projects to improve patient care processes for two specific patient groups were conducted at the Academic Medical Center, a 1,000-bed university hospital in Amsterdam. The BPR consisted of process analysis, identification of bottlenecks and goals for redesign, selection of interventions, and evaluation of effects. After identifying and selecting interventions with the greatest expected benefits, changes were implemented and effects were evaluated. For gynecologic oncology patients, access time (from telephone call to first visit) was reduced from 14 days to changes in communication and planning were sufficient to eliminate bottlenecks in the gynecologic oncology project, the dyspnea project required a radical redesign of processes. Experience since these projects suggests that process redesign may have only marginal impact when the greatest bottleneck occurs, as was the case for the two BPR projects, at the point of access to central diagnostic facilities.

  19. Impact of diagnosis-to-treatment waiting time on survival in esophageal cancer patients – A population-based study in The Netherlands

    NARCIS (Netherlands)

    Visser, E.; van Rossum, P.S.N.; Leeftink, Anne Greetje; Siesling, Sabine; van Hillegersberg, R.; Ruurda, J.P.

    Background The aim of this study was to determine whether the waiting time from diagnosis to treatment with curative intent for esophageal cancer impacts oncologic outcomes. Patients and methods All patients treated by esophagectomy for esophageal carcinoma in 2005–2013 were identified from the

  20. The Effect of the Transition to Home Monitoring for the Diagnosis of OSAS on Test Availability, Waiting Time, Patients’ Satisfaction, and Outcome in a Large Health Provider System

    Directory of Open Access Journals (Sweden)

    Ahmad Safadi

    2014-01-01

    Full Text Available During 2009, the Haifa district of Clalit Health Services (CHS has switched from in-lab polysomnography (PSG to home studies for the diagnosis of obstructive sleep apnea (OSA. We assessed the effects of this change on accessibility, waiting time, satisfaction, costs, and CPAP purchase by the patients. Data regarding sleep studies, CPAP purchase, and waiting times were collected retrospectively from the computerized database of CHS. Patients’ satisfaction was assessed utilizing a telephone questionnaire introduced to a randomized small sample of 70 patients. Comparisons were made between 2007 and 2008 (in-lab PSGs and 2010 and 2011 (when most studies were ambulatory. Of about 650000 insured individuals in the Haifa district of CHS, 1471 sleep studies were performed during 2007-2008 compared to 2794 tests during 2010-2011. The average waiting time was 9.9 weeks in 2007-2008 compared to 1.1 weeks in 2010-2011 (P<0.05. 597 CPAPs were purchased in 2007-2008 compared to 831 in 2010-2011. The overall patients’ satisfaction was similar, but discomfort tended to be higher in the in-laboratory group (4.1 vs 2.7 in a scale of 0–10; P=0.11. Switching to ambulatory diagnosis improved the test accessibility and reduced the waiting times. Patients’ satisfaction remained similarly high. The total direct cost of OSA management was reduced.

  1. The relationship between waiting times and 'adherence' to the Scottish Intercollegiate Guidelines Network 98 guideline in autism spectrum disorder diagnostic services in Scotland.

    Science.gov (United States)

    McKenzie, Karen; Forsyth, Kirsty; O'Hare, Anne; McClure, Iain; Rutherford, Marion; Murray, Aja; Irvine, Linda

    2016-05-01

    The aim of this study was to explore the extent to which the Scottish Intercollegiate Guidelines Network 98 guidelines on the assessment and diagnosis of autism spectrum disorder were adhered to in child autism spectrum disorder diagnostic services in Scotland and whether there was a significant relationship between routine practice which more closely reflected these recommendations (increased adherence) and increased waiting times. Retrospective, cross-sectional case note analysis was applied to data from 80 case notes. Adherence ranged from a possible 0 (no adherence) to 19 (full adherence). Overall, 17/22 of the recommendations were adhered to in over 50 of the 80 cases and in 70 or more cases for 11/22 of the recommendations, with a mean adherence score of 16 (standard deviation = 1.9). No significant correlation was found between adherence and total wait time for untransformed (r = 0.15, p = 0.32) or transformed data (r = 0.12, p = 0.20). The results indicated that the assessment and diagnostic practices were consistent with the relevant Scottish Intercollegiate Guidelines Network 98 guideline recommendations. Increased adherence to the 19 included recommendations was not significantly related to increased total waiting times, indicating that the Scottish Intercollegiate Guidelines Network 98 recommendations have generally been integrated into practice, without a resultant increase in patient waits. © The Author(s) 2015.

  2. Weighing waiting

    Directory of Open Access Journals (Sweden)

    Samuel M. Duncan

    2007-12-01

    Full Text Available People have been shown to delay decision making to wait for missing noninstrumental attribute information --- information that would not have altered their decision if known at the outset --- with this delay originally attributed to uncertainty obscuring one's true preference (Bastardi and Shafir, 1998. To test this account, relative to an alternative that delay arises from low confidence in one's preference (Tykocinski and Ruffle, 2003, we manipulated information certainty and the magnitude of a penalty for delay, the latter intended to reduce the influence of easily resolved sources of delay and to magnify any influence of uncertainty. Contrary to expectations, the results were largely inconsistent with the uncertainty account in that, under a low penalty, delay did not depend on information certainty; and, under a high penalty, delay rate was actually much lower when information was uncertain. To explain the latter, we propose that people use a strategy for resolving choice under uncertainty that does not require establishing a confident preference for each value of the missing information. These findings are related to others in which choice difficulty has been found to be a major source of delay.

  3. Waiting time - an offence?

    DEFF Research Database (Denmark)

    Ludvigsen, Mette Spliid

    2004-01-01

    The purpose of the original study: Patient-culture - a qualitative study among hospitalised patients, which is inspired by the work of Album and Isaksen, is to discover, and describe patients' experiences of informal relations and interpret the meaning of having fellow-patients during hospitalisa......The purpose of the original study: Patient-culture - a qualitative study among hospitalised patients, which is inspired by the work of Album and Isaksen, is to discover, and describe patients' experiences of informal relations and interpret the meaning of having fellow-patients during...... fieldwork is set up consisting of participant observation and interviews.   Based on the qualitative analysis completed to date on a data set consisting of field notes from participant observations and informal interviews I explore patients' social interactions in their day-to-day lives on two adult...

  4. Waiting for surgery: is waiting bad for anyone or everyone?

    Science.gov (United States)

    Sutherland, J M; Liu, G; Crump, R T; Karimuddin, A A

    2017-12-01

    For Canadians, as in many countries, waiting for elective surgery is expected. The duration of the wait raises questions about the maximum amount of time patients should wait for their surgery. The primary objective of this study was to test for a relationship between the length of time patients waited for elective hernia repair surgery and change in patients' self-reported health. This study was based on a prospectively recruited longitudinal cohort of patients waiting for elective hernia repair surgery. Participants completed the PHQ-9, PEG, EQ-5D(3L) generic instruments, and the condition-specific COMI-hernia. Multivariate regression models explored associations between patient-reported outcomes and potential confounders, including age, sex, socio-economic status, and medical comorbidities. There were 118 participants and the modal age group was 61-70 years. The average wait time for participants was 22.5 weeks. There were no relationships between the duration of participants' wait for hernia repair and the change in patients' self-reported health for hernia-specific outcomes or overall health-related quality of life. There are gains in health-related quality of life to be realized by prioritizing symptomatic patients. Participants with greater pre-operative depression, pain, and hernia-related symptoms experienced an improvement in health prior to surgery, though more clarity is needed on the mechanisms that led to improved health. Many countries face problems with wait lists for elective surgery-and few have effective processes for triaging patients. This study shows that duration of time on the wait list was not associated with change in hernia patients' self-reported health.

  5. Evaluation of patients' attitudes to their care during oral and maxillofacial surgical outpatient consultations: the importance of waiting times and quality of interaction between patient and doctor.

    Science.gov (United States)

    Dimovska, E O F; Sharma, S; Trebble, T M

    2016-06-01

    Knowing what patients think about their care is fundamental to the provision of an effective, quality service, and it can help to direct change and reduce costs. Much of the work in oral and maxillofacial departments concerns the treatment of outpatients, but as little is known about what they think about their care, we aimed to find out which aspects were associated with satisfaction. Consecutive patients (n=244) who attended the oral and maxillofacial outpatient department at Southampton University Hospital NHS Foundation Trust over a 7-day period were given a questionnaire to complete before and after their consultation. It included questions with Likert scale responses on environmental, procedural, and interactive aspects of the visit, and a 16-point scale to rank their priorities. A total of 187 patients (77%) completed the questionnaires. No association was found between expected (p=0.93) or actual (p=0.41) waiting times, and 90% of patients were satisfied with their visit. Seeing the doctor, having confidence in the treatment plan, being listened to, and the ability of the doctor to recognise their personal needs, were ranked as important. Environmental and procedural aspects were considered the least important. These findings may be of value in the development of services to improve patient-centred care. Copyright © 2016 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  6. 7 CFR 1.603 - How are time periods computed?

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false How are time periods computed? 1.603 Section 1.603... Licenses General Provisions § 1.603 How are time periods computed? (a) General. Time periods are computed as follows: (1) The day of the act or event from which the period begins to run is not included. (2...

  7. 50 CFR 221.3 - How are time periods computed?

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false How are time periods computed? 221.3... Provisions § 221.3 How are time periods computed? (a) General. Time periods are computed as follows: (1) The day of the act or event from which the period begins to run is not included. (2) The last day of the...

  8. Effectiveness and acceptance of a web-based depression intervention during waiting time for outpatient psychotherapy: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Grünzig, Sasha-Denise; Baumeister, Harald; Bengel, Jürgen; Ebert, David; Krämer, Lena

    2018-05-22

    Due to limited resources, waiting periods for psychotherapy are often long and burdening for those in need of treatment and the health care system. In order to bridge the gap between initial contact and the beginning of psychotherapy, web-based interventions can be applied. The implementation of a web-based depression intervention during waiting periods has the potential to reduce depressive symptoms and enhance well-being in depressive individuals waiting for psychotherapy. In a two-arm randomized controlled trial, effectiveness and acceptance of a guided web-based intervention for depressive individuals on a waitlist for psychotherapy are evaluated. Participants are recruited in several German outpatient clinics. All those contacting the outpatient clinics with the wish to enter psychotherapy receive study information and a depression screening. Those adults (age ≥ 18) with depressive symptoms above cut-off (CES-D scale > 22) and internet access are randomized to either intervention condition (treatment as usual and immediate access to the web-based intervention) or waiting control condition (treatment as usual and delayed access to the web-based intervention). At three points of assessment (baseline, post-treatment, 3-months-follow-up) depressive symptoms and secondary outcomes, such as quality of life, attitudes towards psychotherapy and web-based interventions and adverse events are assessed. Additionally, participants' acceptance of the web-based intervention is evaluated, using measures of intervention adherence and satisfaction. This study investigates a relevant setting for the implementation of web-based interventions, potentially improving the provision of psychological health care. The results of this study contribute to the evaluation of innovative and resource-preserving health care models for outpatient psychological treatment. This trial has been registered on 13 February 2017 in the German clinical trials register (DRKS); registration

  9. On periodic orbits in discrete-time cascade systems

    Directory of Open Access Journals (Sweden)

    Huimin Li

    2006-01-01

    Full Text Available We present some results on existence, minimum period, number of periodic orbits, and stability of periodic orbits in discrete-time cascade systems. Some examples are presented to illustrate these results.

  10. ¿Ha llegado la hora de la gestión de las listas de espera? Has the time arrived for the management of waiting lists?

    Directory of Open Access Journals (Sweden)

    E. Bernal

    2002-10-01

    Full Text Available Las personas que ocupan una lista de espera sufren a menudo un riesgo adicional derivado del tiempo que pasa hasta que obtienen tratamiento; sin embargo, en otras ocasiones, las personas en lista no tienen necesidad del tratamiento por el que esperan. Ambos argumentos, contrastables con evidencias empíricas, serían suficientes para afirmar que debe llegar la gestión a las listas de espera dejando a un lado políticas más o menos oportunistas. Por políticas oportunistas se entiende mantener la mala información sobre listas o su "maquillaje", utilizar programas de autoconcertación sin más horizonte que llegar a final de año sin lista de más de seis meses, etcétera. El panorama no es del todo oscuro. Algunas iniciativas de gestión (incluso de Política con mayúscula se van abriendo paso y pueden entrar en la agenda de los próximos años. Así, cabe destacar la aplicación de tiempos de atención garantizada o la priorización de las listas en función de criterios explícitos. En todo caso, conviene recordar que, con la excepción de las colas producidas en las salas de espera de los centros de salud y aquéllas que se producen en las puertas de urgencias, el resto de colas del sistema están mediadas por la decisión de un médico. Así que una estrategia ineludible para gestionar las listas de espera consiste en atenuar los problemas derivados de la incertidumbre (o ignorancia con respecto al diagnóstico o al pronóstico de los pacientes.Individuals on the waiting list frequently suffer an additional risk caused by the mean time until they receive treatment; however, other individuals do not need the treatment for which they are waiting. Both arguments, which can be contrasted with empirical evidence, would be sufficient to affirm that waiting list management should be implemented, leaving aside policies that are more of less opportunistic. Opportunistic policies are understood as those providing misinformation on waiting lists or

  11. Analysis of emergency department waiting lines

    Directory of Open Access Journals (Sweden)

    Urška Močnik

    2014-10-01

    Full Text Available Background: Steady increase in the numbers of patients seeking medical assistance has recently been observed at the emergency department of the health center under study. This has led to increases in waiting times for patients. The management of the health center has been considering to implement certain measures to remedy this situation. One proposed solution is to add an additional physician to the emergency department. A computer model was constructed to simulate waiting lines and analyze the economic feasibility of employing an additional physician.Aim: This paper analyzes the waiting lines at the emergency department and performs an economic feasibility study to determine whether adding an additional physician to the department would be economically justified.Methods: Data about waiting times at the emergency department were collected to study the situation. For each patient, the arrival time at the waiting room and the starting and ending times of the examination were registered. The data were collected from 13 June 2011 to 25 September 2011. The sample included data on 65 nightly standbys, nine standbys on Saturdays, and 16 standbys on Sundays. Due to incomplete entries, data for nine weekly standbys and six Saturday standbys were excluded from the sample. Based on the data collected, we calculated the waiting and examination times per patient, average number of patients, average waiting time, average examination time, share of active standby teams in total standby time, and number of patients in different time periods. The study involved 1,039 patients. Using a synthesis method, we designed a computer model of waiting lines and economic feasibility. The model was validated using comparative analysis. A what-if analysis was performed using various computer simulations with various scenarios to consider the outcomes of decision alternatives. We applied economic analysis to select the best possible solution.Results: The research results

  12. 43 CFR 45.3 - How are time periods computed?

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false How are time periods computed? 45.3... IN FERC HYDROPOWER LICENSES General Provisions § 45.3 How are time periods computed? (a) General... run is not included. (2) The last day of the period is included. (i) If that day is a Saturday, Sunday...

  13. Consumer behaviour in the waiting area.

    Science.gov (United States)

    Mobach, Mark P

    2007-02-01

    To determine consumer behaviour in the pharmacy waiting area. The applied methods for data-collection were direct observations. Three Dutch community pharmacies were selected for the study. The topics in the observation list were based on available services at each waiting area (brochures, books, illuminated new trailer, children's play area, etc.). Per patient each activity was registered, and at each pharmacy the behaviour was studied for 2 weeks. Most patients only waited during the waiting time at the studied pharmacies. Few consumers obtained written information during their wait. The waiting area may have latent possibilities to expand the information function of the pharmacy and combine this with other activities that distract the consumer from the wait. Transdisciplinary research, combining knowledge from pharmacy practice research with consumer research, has been a useful approach to add information on queueing behaviour of consumers.

  14. Learning to wait

    DEFF Research Database (Denmark)

    Dungey, Claire Elisabeth; Meinert, Lotte

    2017-01-01

    enforced through discipline, prepare young people to expect that waiting and enduring hardship will pay off in the end. This expectation makes the status of adulthood particularly vulnerable because the jobs and opportunities that young men learn to wait for often do not come into being by waiting....

  15. Whittling Down the Wait Time: Exploring Models to Minimize the Delay from Initial Concern to Diagnosis and Treatment of Autism Spectrum Disorder.

    Science.gov (United States)

    Gordon-Lipkin, Eliza; Foster, Jessica; Peacock, Georgina

    2016-10-01

    The process from initial concerns to diagnosis of autism spectrum disorder (ASD) can be a long and complicated process. The traditional model for evaluation and diagnosis of ASD often consists of long wait-lists and evaluations that result in a 2-year difference between the earliest signs of ASD and mean age of diagnosis. Multiple factors contribute to this diagnostic bottleneck, including time-consuming evaluations, cost of care, lack of providers, and lack of comfort of primary care providers to diagnose autism. This article explores innovative clinical models that have been implemented to address this as well as future directions and opportunities. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Waiting for transplant: physical, psychosocial, and nutritional status considerations for pediatric candidates and implications for care.

    Science.gov (United States)

    Anthony, Samantha J; Annunziato, Rachel A; Fairey, Elise; Kelly, Vicky L; So, Stephanie; Wray, Jo

    2014-08-01

    The waiting period for an organ transplant has been described as a time of tremendous uncertainty and vulnerability, posing unique challenges and stressors for pediatric transplant candidates and their families. It has been identified as the most stressful stage of the transplant journey, yet little attention has been given to the physical, psychological, or social impact of the waiting period in the literature. In this review, we discuss the physical, nutritional, and psychosocial implications of the waiting period for child and adolescent transplant candidates and the impact on their parents and siblings. We identify areas for future research and provide recommendations for clinical practice to support children, adolescents, and families during the waiting period. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Waiting for surgery from the patient perspective

    Directory of Open Access Journals (Sweden)

    Tracey Carr

    2009-10-01

    Full Text Available Tracey Carr1, Ulrich Teucher2, Jackie Mann4, Alan G Casson31Health Sciences, 2Department of Psychology, 3Department of Surgery, University of Saskatchewan, Saskatoon, Saskatchewan, Canada; 4Acute Care, Saskatoon Health Region, Saskatoon, Saskatchewan, CanadaAbstract: The aim of this study was to perform a systematic review of the impact of waiting for elective surgery from the patient perspective, with a focus on maximum tolerance, quality of life, and the nature of the waiting experience. Searches were conducted using Medline, PubMed, CINAHL, EMBASE, and HealthSTAR. Twenty-seven original research articles were identified which included each of these three themes. The current literature suggested that first, patients tend to state longer wait times as unacceptable when they experienced severe symptoms or functional impairment. Second, the relationship between length of wait and health-related quality of life depended on the nature and severity of proposed surgical intervention at the time of booking. Third, the waiting experience was consistently described as stressful and anxiety provoking. While many patients expressed anger and frustration at communication within the system, the experience of waiting was not uniformly negative. Some patients experienced waiting as an opportunity to live full lives despite pain and disability. The relatively unexamined relationship between waiting, illness and patient experience of time represents an area for future research.Keywords: wait time, scheduled surgery, patient perspective, literature review

  18. Has the time to come leave the "watch-and-wait" strategy in newly diagnosed asymptomatic follicular lymphoma patients?

    Science.gov (United States)

    Rueda, Antonio; Casanova, María; Redondo, Maximino; Pérez-Ruiz, Elisabeth; Medina-Pérez, Angeles

    2012-05-31

    Historically, the median overall survival for follicular lymphoma (FL) has been considered to be 9-10 years, and no treatment had ever prolonged this time period. Studies conducted more than 20 years ago demonstrated that treating patients with asymptomatic FL at the onset of the disease did not increase their survival, and that almost 20% of these patients did not need any treatment in the first 10 years of follow-up. Based on these facts, most clinical practice guidelines recommend active surveillance policies for patients with asymptomatic FL. The introduction of antiCD-20 monoclonal antibodies, over the last 15 years, has significantly increased the median survival rate to above 14 years. This improvement was achieved before the combination of rituximab and chemotherapy regimens became extensively used in patients with symptomatic disease. Therefore, this increase in survival may currently be more significant. At present, several clinical trials have evaluated low-toxicity therapies that prolong progression-free periods, among which rituximab monotherapy, radioimmunotherapy or the combination of rituximab with bendamustine are the most relevant. Unfortunately, these clinical trials have included only patients with symptomatic FL. The results of a recently reported clinical trial show that treatment with single-agent rituximab prolongs progression-free survival rates, time to new treatment and the quality of life of asymptomatic patients, as compared with the active surveillance strategy. Longer follow-up of these results and data regarding overall survival are awaited before this treatment can be recommended as the standard initial therapy. There are different therapeutic possibilities for asymptomatic FL patients, but no data are currently available to indicate which option is the best. Patients need to understand the risks and benefits of observation versus treatment before a final decision can be made. For patients who want active treatment the

  19. Implementing wait-time reductions under Ontario government benchmarks (Pay-for-Results): a Cluster Randomized Trial of the Effect of a Physician-Nurse Supplementary Triage Assistance team (MDRNSTAT) on emergency department patient wait times.

    Science.gov (United States)

    Cheng, Ivy; Lee, Jacques; Mittmann, Nicole; Tyberg, Jeffrey; Ramagnano, Sharon; Kiss, Alex; Schull, Michael; Kerr, Fergus; Zwarenstein, Merrick

    2013-11-11

    Internationally, emergency departments are struggling with crowding and its associated morbidity, mortality, and decreased patient and health-care worker satisfaction. The objective was to evaluate the addition of a MDRNSTAT (Physician (MD)-Nurse (RN) Supplementary Team At Triage) on emergency department patient flow and quality of care. Pragmatic cluster randomized trial. From 131 weekday shifts (8:00-14:30) during a 26-week period, we randomized 65 days (3173 visits) to the intervention cluster with a MDRNSTAT presence, and 66 days (3163 visits) to the nurse-only triage control cluster. The primary outcome was emergency department length-of-stay (EDLOS) for patients managed and discharged only by the emergency department. Secondary outcomes included EDLOS for patients initially seen by the emergency department, and subsequently consulted and admitted, patients reaching government-mandated thresholds, time to initial physician assessment, left-without being seen rate, time to investigation, and measurement of harm. The intervention's median EDLOS for discharged, non-consulted, high acuity patients was 4:05 [95th% CI: 3:58 to 4:15] versus 4:29 [95th% CI: 4:19-4:38] during comparator shifts. The intervention's median EDLOS for discharged, non-consulted, low acuity patients was 1:55 [95th% CI: 1:48 to 2:05] versus 2:08 [95th% CI: 2:02-2:14]. The intervention's median physician initial assessment time was 0:55 [95th% CI: 0:53 to 0:58] versus 1:21 [95th% CI: 1:18 to 1:25]. The intervention's left-without-being-seen rate was 1.5% versus 2.2% for the control (p = 0.06). The MDRNSTAT subgroup analysis resulted in significant decreases in median EDLOS for discharged, non-consulted high (4:01 [95th% CI: 3:43-4:16]) and low acuity patients (1:10 95th% CI: 0:58-1:19]), as well as physician initial assessment time (0:25 [95th% CI: 0:23-0:26]). No patients returned to the emergency department after being discharged by the MDRNSTAT at triage. The intervention reduced delays

  20. On positive periodic solution of periodic competition Lotka-Volterra system with time delay and diffusion

    International Nuclear Information System (INIS)

    Sun Wen; Chen Shihua; Hong Zhiming; Wang Changping

    2007-01-01

    A two-species periodic competition Lotka-Volterra system with time delay and diffusion is investigated. Some sufficient conditions of the existence of positive periodic solution are established for the system by using the continuation theorem of coincidence degree theory

  1. Almost Periodicity in Time of Solutions of the Toda Lattice

    OpenAIRE

    Binder, Ilia; Damanik, David; Lukic, Milivoje; VandenBoom, Tom

    2016-01-01

    We study an initial value problem for the Toda lattice with almost periodic initial data. We consider initial data for which the associated Jacobi operator is absolutely continuous and has a spectrum satisfying a Craig-type condition, and show the boundedness and almost periodicity in time and space of solutions.

  2. G-quadruplex and G-rich sequence stimulate Pif1p-catalyzed downstream duplex DNA unwinding through reducing waiting time at ss/dsDNA junction

    Science.gov (United States)

    Zhang, Bo; Wu, Wen-Qiang; Liu, Na-Nv; Duan, Xiao-Lei; Li, Ming; Dou, Shuo-Xing; Hou, Xi-Miao; Xi, Xu-Guang

    2016-01-01

    Alternative DNA structures that deviate from B-form double-stranded DNA such as G-quadruplex (G4) DNA can be formed by G-rich sequences that are widely distributed throughout the human genome. We have previously shown that Pif1p not only unfolds G4, but also unwinds the downstream duplex DNA in a G4-stimulated manner. In the present study, we further characterized the G4-stimulated duplex DNA unwinding phenomenon by means of single-molecule fluorescence resonance energy transfer. It was found that Pif1p did not unwind the partial duplex DNA immediately after unfolding the upstream G4 structure, but rather, it would dwell at the ss/dsDNA junction with a ‘waiting time’. Further studies revealed that the waiting time was in fact related to a protein dimerization process that was sensitive to ssDNA sequence and would become rapid if the sequence is G-rich. Furthermore, we identified that the G-rich sequence, as the G4 structure, equally stimulates duplex DNA unwinding. The present work sheds new light on the molecular mechanism by which G4-unwinding helicase Pif1p resolves physiological G4/duplex DNA structures in cells. PMID:27471032

  3. Periodic flows to chaos in time-delay systems

    CERN Document Server

    Luo, Albert C J

    2017-01-01

    This book for the first time examines periodic motions to chaos in time-delay systems, which exist extensively in engineering. For a long time, the stability of time-delay systems at equilibrium has been of great interest from the Lyapunov theory-based methods, where one cannot achieve the ideal results. Thus, time-delay discretization in time-delay systems was used for the stability of these systems. In this volume, Dr. Luo presents an accurate method based on the finite Fourier series to determine periodic motions in nonlinear time-delay systems. The stability and bifurcation of periodic motions are determined by the time-delayed system of coefficients in the Fourier series and the method for nonlinear time-delay systems is equivalent to the Laplace transformation method for linear time-delay systems. Facilitates discovery of analytical solutions of nonlinear time-delay systems; Illustrates bifurcation trees of periodic motions to chaos; Helps readers identify motion complexity and singularity; Explains pro...

  4. New serial time codes for seismic short period and long period data acquisition systems

    International Nuclear Information System (INIS)

    Kolvankar, V.G.; Rao, D.S.

    1988-01-01

    This paper discusses a new time code for time indexing multichannel short period (1 to 25 hz) seismic event data recorded on a single track of magnetic tape in digital format and discusses its usefulness in contrast to Vela time code used in continuous analog multichannel data recording system on multitrack instrumentation tape deck. This paper also discusses another time code, used for time indexing of seismic long period (DC to 2.5 seconds) multichannel data recorded on a single track of magnetic tape in digital format. The time code decoding and display system developed to provide quick access to any desired portion of the tape in both data recording and repro duce system is also discussed. (author). 7 figs

  5. Effective diffusion in time-periodic linear planar flow

    International Nuclear Information System (INIS)

    Indeikina, A.; Chang, H.

    1993-01-01

    It is shown that when a point source of solute is inserted into a time-periodic, unbounded linear planar flow, the large-time, time-average transport of the solute can be described by classical anisotropic diffusion with constant effective diffusion tensors. For a given vorticity and forcing period, elongational flow is shown to be the most dispersive followed by simple shear and rotational flow. Large-time diffusivity along the major axis of the time-average concentration ellipse, whose alignment is predicted from the theory, is shown to increase with vorticity for all flows and decrease with increasing forcing frequency for elongational flow and simple shear. For the interesting case of rotational flow, there exist discrete resonant frequencies where the time-average major diffusivity reaches local maxima equal to the time-average steady flow case with zero forcing frequency

  6. Waiting Online: A Review and Research Agenda.

    Science.gov (United States)

    Ryan, Gerard; Valverde, Mireia

    2003-01-01

    Reviews 21 papers based on 13 separate empirical studies on waiting on the Internet, drawn from the areas of marketing, system response time, and quality of service studies. The article proposes an agenda for future research, including extending the range of research methodologies, broadening the definition of waiting on the Internet, and…

  7. Real time control of the sawtooth period using EC launchers

    International Nuclear Information System (INIS)

    Paley, J I; Felici, F; Coda, S; Goodman, T P; Piras, F

    2009-01-01

    Tokamak plasmas operating at high performance are limited by several MHD instabilities. The sawtooth instability limits the core plasma pressure and can drive the neoclassical tearing mode unstable, but also prevents accumulation of impurities in the core. Electron cyclotron heating and current drive systems can be used to modify the local current profile and therefore tailor the sawtooth period. This paper reports on demonstrations of continuous real time feedback control of the sawtooth period by varying the EC injection angle.

  8. Period doubling phenomenon in a class of time delay equations

    International Nuclear Information System (INIS)

    Oliveira, C.R. de; Malta, C.P.

    1985-01-01

    The properties of the solution of a nonlinear time delayed differential equation (infinite dimension) as function of two parameters: the time delay tau and another parameter A (nonlinearity) are investigated. After a Hopf bifurcation period doubling may occur and is characterized by Feigenbaum's delta. A strange atractor is obtained after the period doubling cascade and the largest Lyapunov exponent is calculated indicating that the attractor has low dimension. The behaviour of this Liapunov exponent as function of tau is different from its behaviour as function of A. (Author) [pt

  9. Measuring border delay and crossing times at the US-Mexico border : part II. Guidebook for analysis and dissemination of border crossing time and wait time data.

    Science.gov (United States)

    2012-06-01

    The purpose of this guidebook is to describe to local, regional, and State agencies how to analyze and disseminate data collected by a radio frequency identification (RFID)-based system to measure travel times of commercial vehicles, which is referre...

  10. 15 CFR 325.4 - Calculating time periods.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Calculating time periods. 325.4 Section 325.4 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE MISCELLANEOUS REGULATIONS EXPORT TRADE CERTIFICATES...

  11. Problems of Software Detection of Periodic Features in a Time ...

    African Journals Online (AJOL)

    Problems arise when attempts are made to extract automatically, visually obvious periodic features indicative of defects in a vibration time series for diagnosis using computers. Such problems may be interpretational in nature arising either from insufficient knowledge of the mechanism, or the convolution of the source signal ...

  12. Commercial border crossing and wait time measurement at Laredo World Trade Bridge and the Colombia-Solidarity Bridge.

    Science.gov (United States)

    2012-03-01

    This research is to establish a baseline and on-going measurement of border crossing times and : delay by measuring travel times for commercial trucks crossing the port of entry (POE) from : Mexico into Texas at the Laredo World Trade Bridge and the ...

  13. Time-periodic solutions of the Benjamin-Ono equation

    Energy Technology Data Exchange (ETDEWEB)

    Ambrose , D.M.; Wilkening, Jon

    2008-04-01

    We present a spectrally accurate numerical method for finding non-trivial time-periodic solutions of non-linear partial differential equations. The method is based on minimizing a functional (of the initial condition and the period) that is positive unless the solution is periodic, in which case it is zero. We solve an adjoint PDE to compute the gradient of this functional with respect to the initial condition. We include additional terms in the functional to specify the free parameters, which, in the case of the Benjamin-Ono equation, are the mean, a spatial phase, a temporal phase and the real part of one of the Fourier modes at t = 0. We use our method to study global paths of non-trivial time-periodic solutions connecting stationary and traveling waves of the Benjamin-Ono equation. As a starting guess for each path, we compute periodic solutions of the linearized problem by solving an infinite dimensional eigenvalue problem in closed form. We then use our numerical method to continue these solutions beyond the realm of linear theory until another traveling wave is reached (or until the solution blows up). By experimentation with data fitting, we identify the analytical form of the solutions on the path connecting the one-hump stationary solution to the two-hump traveling wave. We then derive exact formulas for these solutions by explicitly solving the system of ODE's governing the evolution of solitons using the ansatz suggested by the numerical simulations.

  14. Time-periodic solutions of the Benjamin-Ono equation

    International Nuclear Information System (INIS)

    Ambrose, D.M.; Wilkening, Jon

    2008-01-01

    We present a spectrally accurate numerical method for finding non-trivial time-periodic solutions of non-linear partial differential equations. The method is based on minimizing a functional (of the initial condition and the period) that is positive unless the solution is periodic, in which case it is zero. We solve an adjoint PDE to compute the gradient of this functional with respect to the initial condition. We include additional terms in the functional to specify the free parameters, which, in the case of the Benjamin-Ono equation, are the mean, a spatial phase, a temporal phase and the real part of one of the Fourier modes at t = 0. We use our method to study global paths of non-trivial time-periodic solutions connecting stationary and traveling waves of the Benjamin-Ono equation. As a starting guess for each path, we compute periodic solutions of the linearized problem by solving an infinite dimensional eigenvalue problem in closed form. We then use our numerical method to continue these solutions beyond the realm of linear theory until another traveling wave is reached (or until the solution blows up). By experimentation with data fitting, we identify the analytical form of the solutions on the path connecting the one-hump stationary solution to the two-hump traveling wave. We then derive exact formulas for these solutions by explicitly solving the system of ODE's governing the evolution of solitons using the ansatz suggested by the numerical simulations

  15. Using Tic-Tac Software to Reduce Anxiety-Related Behaviour in Adults with Autism and Learning Difficulties during Waiting Periods: A Pilot Study

    Science.gov (United States)

    Campillo, Cristina; Herrera, Gerardo; Remírez de Ganuza, Conchi; Cuesta, José L.; Abellán, Raquel; Campos, Arturo; Navarro, Ignacio; Sevilla, Javier; Pardo, Carlos; Amati, Fabián

    2014-01-01

    Deficits in the perception of time and processing of changes across time are commonly observed in individuals with autism. This pilot study evaluated the efficacy of the use of the software tool Tic-Tac, designed to make time visual, in three adults with autism and learning difficulties. This research focused on applying the tool in waiting…

  16. Unstable Periodic Orbit Analysis of Histograms of Chaotic Time Series

    International Nuclear Information System (INIS)

    Zoldi, S.M.

    1998-01-01

    Using the Lorenz equations, we have investigated whether unstable periodic orbits (UPOs) associated with a strange attractor may predict the occurrence of the robust sharp peaks in histograms of some experimental chaotic time series. Histograms with sharp peaks occur for the Lorenz parameter value r=60.0 but not for r=28.0 , and the sharp peaks for r=60.0 do not correspond to a histogram derived from any single UPO. However, we show that histograms derived from the time series of a non-Axiom-A chaotic system can be accurately predicted by an escape-time weighting of UPO histograms. copyright 1998 The American Physical Society

  17. Time analysis in astronomy: Tools for periodicity searches

    International Nuclear Information System (INIS)

    Buccheri, R.; Sacco, B.

    1985-01-01

    The authors discuss periodicity searches in radio and gamma-ray astronomy with special considerations for pulsar searches. The basic methodologies of fast Fourier transform, Rayleigh test, and epoch folding are reviewed with the main objective to compare cost and sensitivities in different applications. It is found that FFT procedures are convenient in unbiased searches for periodicity in radio astronomy, while in spark chamber gamma-ray astronomy, where the measurements are spread over a long integration time, unbiased searches are very difficult with the existing computing facilities and analyses with a-priori knowledge on the period values to look for are better done using the Rayleigh test with harmonics folding (Z /sub n/ test)

  18. Computing return times or return periods with rare event algorithms

    Science.gov (United States)

    Lestang, Thibault; Ragone, Francesco; Bréhier, Charles-Edouard; Herbert, Corentin; Bouchet, Freddy

    2018-04-01

    The average time between two occurrences of the same event, referred to as its return time (or return period), is a useful statistical concept for practical applications. For instance insurances or public agencies may be interested by the return time of a 10 m flood of the Seine river in Paris. However, due to their scarcity, reliably estimating return times for rare events is very difficult using either observational data or direct numerical simulations. For rare events, an estimator for return times can be built from the extrema of the observable on trajectory blocks. Here, we show that this estimator can be improved to remain accurate for return times of the order of the block size. More importantly, we show that this approach can be generalised to estimate return times from numerical algorithms specifically designed to sample rare events. So far those algorithms often compute probabilities, rather than return times. The approach we propose provides a computationally extremely efficient way to estimate numerically the return times of rare events for a dynamical system, gaining several orders of magnitude of computational costs. We illustrate the method on two kinds of observables, instantaneous and time-averaged, using two different rare event algorithms, for a simple stochastic process, the Ornstein–Uhlenbeck process. As an example of realistic applications to complex systems, we finally discuss extreme values of the drag on an object in a turbulent flow.

  19. The impact of nurse practitioner services on cost, quality of care, satisfaction and waiting times in the emergency department: a systematic review.

    Science.gov (United States)

    Jennings, Natasha; Clifford, Stuart; Fox, Amanda R; O'Connell, Jane; Gardner, Glenn

    2015-01-01

    To provide the best available evidence to determine the impact of nurse practitioner services on cost, quality of care, satisfaction and waiting times in the emergency department for adult patients. The delivery of quality care in the emergency department is emerging as one of the most important service indicators in health delivery. Increasing service pressures in the emergency department have resulted in the adoption of service innovation models: the most common and rapidly expanding of these is emergency nurse practitioner services. The rapid uptake of emergency nurse practitioner service in Australia has outpaced the capacity to evaluate this service model in terms of outcomes related to safety and quality of patient care. Previous research is now outdated and not commensurate with the changing domain of delivering emergency care with nurse practitioner services. A comprehensive search of four electronic databases from 2006 to 2013 was conducted to identify research evaluating nurse practitioner service impact in the emergency department. English language articles were sought using MEDLINE, CINAHL, Embase and Cochrane and included two previous systematic reviews completed five and seven years ago. A three step approach was used. Following a comprehensive search, two reviewers assessed all identified studies against the inclusion criteria. From the original 1013 studies, 14 papers were retained for critical appraisal on methodological quality by two independent reviewers and data were extracted using standardised tools. Narrative synthesis was conducted to summarise and report the findings as insufficient data was available for meta-analysis of results. This systematic review has shown that emergency nurse practitioner service has a positive impact on quality of care, patient satisfaction and waiting times. There was insufficient evidence to draw conclusions regarding outcomes of a cost benefit analysis. Synthesis of the available research attempts to provide an

  20. Mimicking Nonequilibrium Steady States with Time-Periodic Driving

    Science.gov (United States)

    2016-08-29

    construction does not require the solution of any differential equations , only linear algebraic equations . By contrast, a mapping in the opposite...set of algebraic linear equations . The mapping between NESS and SP presented above was not intended as a set of operational instructions for... differential equations with time-periodic parameters. Typically, this can only be done numerically. In some applications, transition rates are constrained by

  1. Periodic solutions in reaction–diffusion equations with time delay

    International Nuclear Information System (INIS)

    Li, Li

    2015-01-01

    Spatial diffusion and time delay are two main factors in biological and chemical systems. However, the combined effects of them on diffusion systems are not well studied. As a result, we investigate a nonlinear diffusion system with delay and obtain the existence of the periodic solutions using coincidence degree theory. Moreover, two numerical examples confirm our theoretical results. The obtained results can also be applied in other related fields

  2. Costly waiting for the future gas energy

    International Nuclear Information System (INIS)

    1999-01-01

    The article discusses solutions while waiting for the pollution free gas power plant and points out that Norway will have to import Danish power from coal and Swedish nuclear energy for a long time yet. Various future scenarios are mentioned

  3. Waiting times for the appearance of cytotoxic T-lymphocyte escape mutants in chronic HIV-1 infection

    International Nuclear Information System (INIS)

    Liu Yi; Mullins, James I.; Mittler, John E.

    2006-01-01

    The failure of HIV-1 to escape at some cytotoxic T-lymphocyte (CTL) epitopes has generally been explained in terms of viral fitness costs or ineffective or attenuated CTL responses. Relatively little attention has been paid to the evolutionary time required for escape mutants to be detected. This time is significantly affected by selection, mutation rates, the presence of other advantageous mutations, and the effective population size of HIV-1 in vivo (typically estimated to be ∼10 3 in chronically infected patients, though one study has estimated it to be ∼10 5 ). Here, we use a forward simulator with experimentally estimated HIV-1 parameters to show that these delays can be substantial. For an effective population size of 10 3 , even highly advantageous mutants (s = 0.5) may not be detected for a couple of years in chronically infected patients, while moderately advantageous escape mutants (s = 0.1) may not be detected for up to 10 years. Even with an effective population size of 10 5 , a moderately advantageous escape mutant (s = 0.1) may not be detected in the population within 2 years if it has to compete with other selectively advantageous mutants. Stochastic evolutionary forces, therefore, in addition to viral fitness costs and ineffective or attenuated CTL responses, must be taken into account when assessing the selection of CTL escape mutations

  4. Periodicity and stability for variable-time impulsive neural networks.

    Science.gov (United States)

    Li, Hongfei; Li, Chuandong; Huang, Tingwen

    2017-10-01

    The paper considers a general neural networks model with variable-time impulses. It is shown that each solution of the system intersects with every discontinuous surface exactly once via several new well-proposed assumptions. Moreover, based on the comparison principle, this paper shows that neural networks with variable-time impulse can be reduced to the corresponding neural network with fixed-time impulses under well-selected conditions. Meanwhile, the fixed-time impulsive systems can be regarded as the comparison system of the variable-time impulsive neural networks. Furthermore, a series of sufficient criteria are derived to ensure the existence and global exponential stability of periodic solution of variable-time impulsive neural networks, and to illustrate the same stability properties between variable-time impulsive neural networks and the fixed-time ones. The new criteria are established by applying Schaefer's fixed point theorem combined with the use of inequality technique. Finally, a numerical example is presented to show the effectiveness of the proposed results. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. The Wait Calculation: The Broader Consequences of the Minimum Time from Now to Interstellar Destinations and its Significance to the Space Economy

    Science.gov (United States)

    Kennedy, A.

    This paper summarises the wait calculation [1] of interstellar voyagers which finds the minimum time to destination given exponential growth in the rate of travel available to a civilisation. The minimum time obliges stellar system colonisers to consider departure times a significant risk factor in their voyages since a departure then to a destination will beat a departure made at any other time before or after. Generalised conclusions will be drawn about the significant impact that departures to interstellar destinations before, at, or after the minimum time will have on the economic potential of missions and on the inevitability of competition between them. There will be no international law operating in interstellar space and an ability to escape predatory actions en route, or at the destination, can only be done by precise calculations of departure times. Social and economic forces affecting the factors in the growth equation are discussed with reference to the probability of accelerating growth reaching the technological Singularity and strengthening the growth incentive trap. Islamic banking practices are discussed as a credible alternative to compounding interest bearing paper for funding the space economy in the long term and for supporting stakeholder investment in such long term mission development. The paper considers the essential free productivity of the Earth's biosphere and the capital accumulations made possible by land productivity are essential components to a viable long term space economy and that research into re-creating the costless productivity of the biosphere at a destination will determine both the mission's ultimate success and provide means of returns for stakeholders during the long build up. Conclusions of these arguments suggest that the Icarus project should ignore a robotic interstellar mission concept and develop a manned colonising mission from now.

  6. The study of waiting time to first pregnancy in the south of Iran: A parametric frailty model approach

    Directory of Open Access Journals (Sweden)

    Najaf Zare

    2017-08-01

    Full Text Available Background: Time to first pregnancy (TTFP has never been studied in an Iranian setting. Lifestyle, occupational and environmental factors have been suggested to affect the female reproduction. Objective: This study was conducted to measure TTFP in the south of Iran and survey the effects of several similar factors on TTFP by frailty models. Materials and Methods: The data on TTFP were available for 882 women who were randomly selected from the rural population (the south of Iran. Only the first and the planned pregnancies of every woman were included. The data were collected retrospectively by using self-administered questionnaires. Frailty and shared frailty models were used to determine which factors had the highest impact on TTFP. Results: The median TTFP was 6.4 months and several factors were surveyed. However, only the age of marriage, height, maternal education and regularity of menstruation prior to conception were selected in the multivariable models. Conclusion: Among the several factors which were included in the study, the result of frailty model showed that the height, age of marriage and regular menstruation seemed more notable predictors of TTFP.

  7. The Effect of 5S-Continuous Quality Improvement-Total Quality Management Approach on Staff Motivation, Patients' Waiting Time and Patient Satisfaction with Services at Hospitals in Uganda.

    Science.gov (United States)

    Take, Naoki; Byakika, Sarah; Tasei, Hiroshi; Yoshikawa, Toru

    2015-03-31

    This study aimed at analyzing the effect of 5S practice on staff motivation, patients' waiting time and patient satisfaction with health services at hospitals in Uganda. Double-difference estimates were measured for 13 Regional Referral Hospitals and eight General Hospitals implementing 5S practice separately. The study for Regional Referral Hospitals revealed 5S practice had the effect on staff motivation in terms of commitment to work in the current hospital and waiting time in the dispensary in 10 hospitals implementing 5S, but significant difference was not identified on patient satisfaction. The study for General Hospitals indicated the effect of 5S practice on patient satisfaction as well as waiting time, but staff motivation in two hospitals did not improve. 5S practice enables the hospitals to improve the quality of services in terms of staff motivation, waiting time and patient satisfaction and it takes as least four years in Uganda. The fourth year since the commencement of 5S can be a threshold to move forward to the next step, Continuous Quality Improvement.

  8. Strategy as active waiting.

    Science.gov (United States)

    Sull, Donald N

    2005-09-01

    Successful executives who cut their teeth in stable industries or in developed countries often stumble when they face more volatile markets. They falter, in part, because they assume they can gaze deep into the future and develop a long-term strategy that will confer a sustainable competitive advantage. But visibility into the future of volatile markets is sharply limited because so many different variables are in play. Factors such as technological innovation, customers' evolving needs, government policy, and changes in the capital markets interact with one another to create unexpected outcomes. Over the past six years, Donald Sull, an associate professor at London Business School, has led a research project examining some of the world's most volatile markets, from national markets like China and Brazil to industries like enterprise software, telecommunications, and airlines. One of the most striking findings from this research is the importance of taking action during comparative lulls in the storm. Huge business opportunities are relatively rare; they come along only once or twice in a decade. And, for the most part, companies can't manufacture those opportunities; changes in the external environment converge to make them happen. What managers can do is prepare for these golden opportunities by managing smart during the comparative calm of business as usual. During these periods of active waiting, leaders must probe the future and remain alert to anomalies that signal potential threats or opportunities; exercise restraint to preserve their war chests; and maintain discipline to keep the troops battle ready. When a golden opportunity or"sudden death"threat emerges, managers must have the courage to declare the main effort and concentrate resources to seize the moment.

  9. Who breaches the four-hour emergency department wait time target? A retrospective analysis of 374,000 emergency department attendances between 2008 and 2013 at a type 1 emergency department in England.

    Science.gov (United States)

    Bobrovitz, Niklas; Lasserson, Daniel S; Briggs, Adam D M

    2017-11-02

    The four-hour target is a key hospital emergency department performance indicator in England and one that drives the physical and organisational design of the ED. Some studies have identified time of presentation as a key factor affecting waiting times. Few studies have investigated other determinants of breaching the four-hour target. Therefore, our objective was to describe patterns of emergency department breaches of the four-hour wait time target and identify patients at highest risk of breaching. This was a retrospective cohort study of a large type 1 Emergency department at an NHS teaching hospital in Oxford, England. We analysed anonymised individual level patient data for 378,873 emergency department attendances, representing all attendances between April 2008 and April 2013. We examined patient characteristics and emergency department presentation circumstances associated with the highest likelihood of breaching the four-hour wait time target. We used 374,459 complete cases for analysis. In total, 8.3% of all patients breached the four-hour wait time target. The main determinants of patients breaching the four-hour wait time target were hour of arrival to the ED, day of the week, patient age, ED referral source, and the types of investigations patients receive (p target were older, presented at night, presented on Monday, received multiple types of investigation in the emergency department, and were not self-referred (p target including patient age, ED referral source, the types of investigations patients receive, as well as the hour, day, and month of arrival to the ED. Efforts to reduce the number of breaches could explore late-evening/overnight staffing, access to diagnostic tests, rapid discharge facilities, and early assessment and input on diagnostic and management strategies from a senior practitioner.

  10. Transient habitats limit development time for periodical cicadas.

    Science.gov (United States)

    Karban, Richard

    2014-01-01

    Periodical cicadas (Magicicada spp.) mature in 13 or 17 years, the longest development times for any non-diapausing insects. Selection may favor prolonged development since nymphs experience little mortality and individuals taking 17 years have been shown to have greater fecundity than those taking 13 years. Why don't periodical cicadas take even longer to develop? Nymphs feed on root xylem fluid and move little. Ovipositing females prefer fast-growing trees at forest edges. I hypothesized that (1) adults emerging at edges would be heavier than those from forest interiors and (2) habitat changes could limit development time. I collected newly eclosed females that had neither fed as adults nor moved from their site of development. For M. septendecim, females from edges were 4.9% heavier than those from the interior. I assumed that emergence density indicated habitat quality and measured density at eight sites in 1979, 1996, and 2013. Over three generations, variation in densities was great; densities at two sites crashed, and at one site they exploded to 579/m2 Habitat transience may limit development time because only adults can reassess habitats and reposition offspring. In conclusion, cicadas are affected by habitat characteristics, habitats change over 17 years, and cicadas may emerge, mate, and redistribute their offspring to track habitat dynamics.

  11. Lagrangian structures in time-periodic vortical flows

    Directory of Open Access Journals (Sweden)

    S. V. Kostrykin

    2006-01-01

    Full Text Available The Lagrangian trajectories of fluid particles are experimentally studied in an oscillating four-vortex velocity field. The oscillations occur due to a loss of stability of a steady flow and result in a regular reclosure of streamlines between the vortices of the same sign. The Eulerian velocity field is visualized by tracer displacements over a short time period. The obtained data on tracer motions during a number of oscillation periods show that the Lagrangian trajectories form quasi-regular structures. The destruction of these structures is determined by two characteristic time scales: the tracers are redistributed sufficiently fast between the vortices of the same sign and much more slowly transported into the vortices of opposite sign. The observed behavior of the Lagrangian trajectories is quantitatively reproduced in a new numerical experiment with two-dimensional model of the velocity field with a small number of spatial harmonics. A qualitative interpretation of phenomena observed on the basis of the theory of adiabatic chaos in the Hamiltonian systems is given. The Lagrangian trajectories are numerically simulated under varying flow parameters. It is shown that the spatial-temporal characteristics of the Lagrangian structures depend on the properties of temporal change in the streamlines topology and on the adiabatic parameter corresponding to the flow. The condition for the occurrence of traps (the regions where the Lagrangian particles reside for a long time is obtained.

  12. Development of a minimization instrument for allocation of a hospital-level performance improvement intervention to reduce waiting times in Ontario emergency departments

    Directory of Open Access Journals (Sweden)

    Anderson Geoff

    2009-06-01

    Full Text Available Abstract Background Rigorous evaluation of an intervention requires that its allocation be unbiased with respect to confounders; this is especially difficult in complex, system-wide healthcare interventions. We developed a short survey instrument to identify factors for a minimization algorithm for the allocation of a hospital-level intervention to reduce emergency department (ED waiting times in Ontario, Canada. Methods Potential confounders influencing the intervention's success were identified by literature review, and grouped by healthcare setting specific change stages. An international multi-disciplinary (clinical, administrative, decision maker, management panel evaluated these factors in a two-stage modified-delphi and nominal group process based on four domains: change readiness, evidence base, face validity, and clarity of definition. Results An original set of 33 factors were identified from the literature. The panel reduced the list to 12 in the first round survey. In the second survey, experts scored each factor according to the four domains; summary scores and consensus discussion resulted in the final selection and measurement of four hospital-level factors to be used in the minimization algorithm: improved patient flow as a hospital's leadership priority; physicians' receptiveness to organizational change; efficiency of bed management; and physician incentives supporting the change goal. Conclusion We developed a simple tool designed to gather data from senior hospital administrators on factors likely to affect the success of a hospital patient flow improvement intervention. A minimization algorithm will ensure balanced allocation of the intervention with respect to these factors in study hospitals.

  13. Development of a minimization instrument for allocation of a hospital-level performance improvement intervention to reduce waiting times in Ontario emergency departments.

    Science.gov (United States)

    Leaver, Chad Andrew; Guttmann, Astrid; Zwarenstein, Merrick; Rowe, Brian H; Anderson, Geoff; Stukel, Therese; Golden, Brian; Bell, Robert; Morra, Dante; Abrams, Howard; Schull, Michael J

    2009-06-08

    Rigorous evaluation of an intervention requires that its allocation be unbiased with respect to confounders; this is especially difficult in complex, system-wide healthcare interventions. We developed a short survey instrument to identify factors for a minimization algorithm for the allocation of a hospital-level intervention to reduce emergency department (ED) waiting times in Ontario, Canada. Potential confounders influencing the intervention's success were identified by literature review, and grouped by healthcare setting specific change stages. An international multi-disciplinary (clinical, administrative, decision maker, management) panel evaluated these factors in a two-stage modified-delphi and nominal group process based on four domains: change readiness, evidence base, face validity, and clarity of definition. An original set of 33 factors were identified from the literature. The panel reduced the list to 12 in the first round survey. In the second survey, experts scored each factor according to the four domains; summary scores and consensus discussion resulted in the final selection and measurement of four hospital-level factors to be used in the minimization algorithm: improved patient flow as a hospital's leadership priority; physicians' receptiveness to organizational change; efficiency of bed management; and physician incentives supporting the change goal. We developed a simple tool designed to gather data from senior hospital administrators on factors likely to affect the success of a hospital patient flow improvement intervention. A minimization algorithm will ensure balanced allocation of the intervention with respect to these factors in study hospitals.

  14. Typical Periods for Two-Stage Synthesis by Time-Series Aggregation with Bounded Error in Objective Function

    Energy Technology Data Exchange (ETDEWEB)

    Bahl, Björn; Söhler, Theo; Hennen, Maike; Bardow, André, E-mail: andre.bardow@ltt.rwth-aachen.de [Institute of Technical Thermodynamics, RWTH Aachen University, Aachen (Germany)

    2018-01-08

    Two-stage synthesis problems simultaneously consider here-and-now decisions (e.g., optimal investment) and wait-and-see decisions (e.g., optimal operation). The optimal synthesis of energy systems reveals such a two-stage character. The synthesis of energy systems involves multiple large time series such as energy demands and energy prices. Since problem size increases with the size of the time series, synthesis of energy systems leads to complex optimization problems. To reduce the problem size without loosing solution quality, we propose a method for time-series aggregation to identify typical periods. Typical periods retain the chronology of time steps, which enables modeling of energy systems, e.g., with storage units or start-up cost. The aim of the proposed method is to obtain few typical periods with few time steps per period, while accurately representing the objective function of the full time series, e.g., cost. Thus, we determine the error of time-series aggregation as the cost difference between operating the optimal design for the aggregated time series and for the full time series. Thereby, we rigorously bound the maximum performance loss of the optimal energy system design. In an initial step, the proposed method identifies the best length of typical periods by autocorrelation analysis. Subsequently, an adaptive procedure determines aggregated typical periods employing the clustering algorithm k-medoids, which groups similar periods into clusters and selects one representative period per cluster. Moreover, the number of time steps per period is aggregated by a novel clustering algorithm maintaining chronology of the time steps in the periods. The method is iteratively repeated until the error falls below a threshold value. A case study based on a real-world synthesis problem of an energy system shows that time-series aggregation from 8,760 time steps to 2 typical periods with each 2 time steps results in an error smaller than the optimality gap of

  15. Organ Type and Waiting Time

    Science.gov (United States)

    ... to know FAQ Living donation What is living donation? Organs Types Being a living donor First steps Being ... There are many financial resources for transplants. Living donation increases the existing organ supply. It’s important to get to know your ...

  16. Reactions to waiting online by men and women.

    Science.gov (United States)

    Chebat, Jean-Charles; Salem, Narjes Haj; Poirier, Jean-François; Gélinas-Chebat, Claire

    2010-06-01

    The goal of the present study was to identify factors which may affect the difference between the actual time participants expected to wait for downloading a web page and the perceived waiting time, i.e., the online waiting-time gap. The findings from an experiment in which the music tempo (fast vs. slow) and waiting-duration information (presence vs. absence) were manipulated showed that sex moderated the relation between the manipulated variables and waiting-time gap; emotional response was more important between the manipulated variables and waiting-time gap than was cognitive response. The type of emotional response with an effect on waiting-time gap varied by sex: pleasure for women and arousal for men. For women, pleasure was affected by their cognitive response, while cognitive response played no significant role for men. For both sexes, information on waiting duration increased the perceived waiting time. This study leads to reconsidering the role of emotional response and sex in evaluating waiting time.

  17. Waiting in the surgery.

    Science.gov (United States)

    Fry, F

    1994-07-01

    The concise Oxford English Dictionary defines 'dilemma' as an argument forcing one to choose one of two alternatives, both of which are unfavourable. This is a situation that frequently confronts the general practitioner. This paper will present one practitioner's view on the subject of patients waiting to see the doctor.

  18. wait and wipe

    African Journals Online (AJOL)

    and wipe strategy” as an alternative to circumcision for HIV prevention. In this paper, we argue that waiting for ten minutes and wiping with a dry cloth does not prevent men from becoming infected by HIV. We ... HIV infected despite having reported no sex or 100% condom .... In a qualitative study conducted in Kenya, men.

  19. Challenging "Waiting for Superman"

    Science.gov (United States)

    Bruhn, Molle

    2014-01-01

    A group of New York City public school teachers, angry about the depiction of public schools in 'Waiting for Superman," decide to make their own film about the realities of the current education reform movement. They persevered even though they had no budget when they started and lacked a background in filmmaking. "The Inconvenient Truth…

  20. Colour Consideration for Waiting areas in hospitals

    Science.gov (United States)

    Zraati, Parisa

    2012-08-01

    Colour is one the most important factors in the nature that can have some affects on human behaviour. Many years ago, it was proven that using colour in public place can have some affect on the users. Depend of the darkness and lightness; it can be vary from positive to negative. The research will mainly focus on the colour and psychological influences and physical factors. The statement of problem in this research is what is impact of colour usually applied to waiting area? The overall aim of the study is to explore the visual environment of hospitals and to manage the colour psychological effect of the hospital users in the waiting area by creating a comfortable, pleasant and cozy environment for users while spend their time in waiting areas. The analysisconcentrate on satisfaction and their interesting regarding applied colour in two private hospital waiting area in Malaysia.

  1. Workshop: Waiting for the top quark

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    The world of elementary particle physics is eagerly waiting for the top quark, probably the final element of the 'periodic table' of elementary particle constituents. This table consists of two families of weakly interacting particles (leptons) - one series carrying electric charge; the other being electrically neutral - together with a family of quarks carrying electric charge 2/3 (up, charm, top) and a family of charge -1/3 quarks (down, strange, beauty). It was then not surprising that the 1990 Theory Workshop at the DESY Laboratory in Hamburg in October, devoted this time to 'top physics', attracted some 200 physicists, substantially more than previous workshops in the series

  2. Solving no-wait two-stage flexible flow shop scheduling problem with unrelated parallel machines and rework time by the adjusted discrete Multi Objective Invasive Weed Optimization and fuzzy dominance approach

    Energy Technology Data Exchange (ETDEWEB)

    Jafarzadeh, Hassan; Moradinasab, Nazanin; Gerami, Ali

    2017-07-01

    Adjusted discrete Multi-Objective Invasive Weed Optimization (DMOIWO) algorithm, which uses fuzzy dominant approach for ordering, has been proposed to solve No-wait two-stage flexible flow shop scheduling problem. Design/methodology/approach: No-wait two-stage flexible flow shop scheduling problem by considering sequence-dependent setup times and probable rework in both stations, different ready times for all jobs and rework times for both stations as well as unrelated parallel machines with regards to the simultaneous minimization of maximum job completion time and average latency functions have been investigated in a multi-objective manner. In this study, the parameter setting has been carried out using Taguchi Method based on the quality indicator for beater performance of the algorithm. Findings: The results of this algorithm have been compared with those of conventional, multi-objective algorithms to show the better performance of the proposed algorithm. The results clearly indicated the greater performance of the proposed algorithm. Originality/value: This study provides an efficient method for solving multi objective no-wait two-stage flexible flow shop scheduling problem by considering sequence-dependent setup times, probable rework in both stations, different ready times for all jobs, rework times for both stations and unrelated parallel machines which are the real constraints.

  3. Solving no-wait two-stage flexible flow shop scheduling problem with unrelated parallel machines and rework time by the adjusted discrete Multi Objective Invasive Weed Optimization and fuzzy dominance approach

    International Nuclear Information System (INIS)

    Jafarzadeh, Hassan; Moradinasab, Nazanin; Gerami, Ali

    2017-01-01

    Adjusted discrete Multi-Objective Invasive Weed Optimization (DMOIWO) algorithm, which uses fuzzy dominant approach for ordering, has been proposed to solve No-wait two-stage flexible flow shop scheduling problem. Design/methodology/approach: No-wait two-stage flexible flow shop scheduling problem by considering sequence-dependent setup times and probable rework in both stations, different ready times for all jobs and rework times for both stations as well as unrelated parallel machines with regards to the simultaneous minimization of maximum job completion time and average latency functions have been investigated in a multi-objective manner. In this study, the parameter setting has been carried out using Taguchi Method based on the quality indicator for beater performance of the algorithm. Findings: The results of this algorithm have been compared with those of conventional, multi-objective algorithms to show the better performance of the proposed algorithm. The results clearly indicated the greater performance of the proposed algorithm. Originality/value: This study provides an efficient method for solving multi objective no-wait two-stage flexible flow shop scheduling problem by considering sequence-dependent setup times, probable rework in both stations, different ready times for all jobs, rework times for both stations and unrelated parallel machines which are the real constraints.

  4. Impact of UCSF criteria according to pre- and post-OLT tumor features: analysis of 479 patients listed for HCC with a short waiting time.

    Science.gov (United States)

    Decaens, Thomas; Roudot-Thoraval, Françoise; Hadni-Bresson, Solange; Meyer, Carole; Gugenheim, Jean; Durand, Francois; Bernard, Pierre-Henri; Boillot, Olivier; Sulpice, Laurent; Calmus, Yvon; Hardwigsen, Jean; Ducerf, Christian; Pageaux, Georges-Philippe; Dharancy, Sebastien; Chazouilleres, Olivier; Cherqui, Daniel; Duvoux, Christophe

    2006-12-01

    Orthotopic liver transplantation (OLT) indication for hepatocellular carcinoma (HCC) is currently based on the Milan criteria. The University of California, San Francisco (UCSF) recently proposed an expansion of the selection criteria according to tumors characteristics on the explanted liver. This study: 1) assessed the validity of these criteria in an independent large series and 2) tested for the usefulness of these criteria when applied to pre-OLT tumor evaluation. Between 1985 and 1998, 479 patients were listed for liver transplantation (LT) for HCC and 467 were transplanted. According to pre-OLT (imaging at date of listing) or post-OLT (explanted liver) tumor characteristics, patients were retrospectively classified according to both the Milan and UCSF criteria. The 5-yr survival statistics were assessed by the Kaplan-Meier method and compared by the log-rank test. Pre-OLT UCSF criteria were analyzed according to an intention-to-treat principle. Based on the pre-OLT evaluation, 279 patients were Milan+, 44 patients were UCSF+ but Milan- (subgroup of patients that might benefit from the expansion), and 145 patients were UCSF- and Milan-. With a short median waiting time of 4 months, 5-yr survival was 60.1 +/- 3.0%, 45.6 +/- 7.8%, and 34.7 +/- 4.0%, respectively (P OLT evaluation, the UCSF criteria are associated with a 5-yr survival below 50%. Their applicability is therefore limited, despite similar survival rates compared to the Milan criteria, when the explanted liver is taken into account.

  5. Unsupervised Ensemble Anomaly Detection Using Time-Periodic Packet Sampling

    Science.gov (United States)

    Uchida, Masato; Nawata, Shuichi; Gu, Yu; Tsuru, Masato; Oie, Yuji

    We propose an anomaly detection method for finding patterns in network traffic that do not conform to legitimate (i.e., normal) behavior. The proposed method trains a baseline model describing the normal behavior of network traffic without using manually labeled traffic data. The trained baseline model is used as the basis for comparison with the audit network traffic. This anomaly detection works in an unsupervised manner through the use of time-periodic packet sampling, which is used in a manner that differs from its intended purpose — the lossy nature of packet sampling is used to extract normal packets from the unlabeled original traffic data. Evaluation using actual traffic traces showed that the proposed method has false positive and false negative rates in the detection of anomalies regarding TCP SYN packets comparable to those of a conventional method that uses manually labeled traffic data to train the baseline model. Performance variation due to the probabilistic nature of sampled traffic data is mitigated by using ensemble anomaly detection that collectively exploits multiple baseline models in parallel. Alarm sensitivity is adjusted for the intended use by using maximum- and minimum-based anomaly detection that effectively take advantage of the performance variations among the multiple baseline models. Testing using actual traffic traces showed that the proposed anomaly detection method performs as well as one using manually labeled traffic data and better than one using randomly sampled (unlabeled) traffic data.

  6. Iran - waiting and watching

    International Nuclear Information System (INIS)

    Malhotra, T. C.

    2007-01-01

    Global oil companies are reported to be divided on the issue of possible energy deals in Iran. Some companies may adopt wait and watch policy before singing a fresh deal with Iran, but there are some oil companies, those are still interested to sign a deal with Iran, despite the risks, even as Tehran decided to expand its uranium enrichment programme rather than complying with a UN Security Council ultimatum to freeze it, which clears the path for further harsher sanctions (author) (ml)

  7. Change in hearing during 'wait and scan' management of patients with vestibular schwannoma

    DEFF Research Database (Denmark)

    Stangerup, Sven-Eric; Caye-Thomasen, P.; Tos, M.

    2008-01-01

    : At the time of diagnosis, 334 patients (53 per cent) had good hearing and speech discrimination of better than 70 per cent; at the end of the 10-year observation period, this latter percentage was 31 per cent. In 17 per cent of the patients, speech discrimination at diagnosis was 100 per cent; of these, 88......Aim: To evaluate hearing changes during 'wait and scan' management of patients with vestibular schwannoma. Subjects: Over a 10-year period, 636 patients have prospectively been allocated to 'wait and scan' management, with annual magnetic resonance scanning and audiological examination. Results...... surgery and of radiation therapy with those of 'wait and scan' management, it appears that, in vestibular schwannoma patients with a small tumour and normal speech discrimination, the main indication for active treatment should be established tumour growth Udgivelsesdato: 2008/7...

  8. 'Waiting for' and 'waiting in' public and private hospitals: a qualitative study of patient trust in South Australia.

    Science.gov (United States)

    Ward, Paul R; Rokkas, Philippa; Cenko, Clinton; Pulvirenti, Mariastella; Dean, Nicola; Carney, A Simon; Meyer, Samantha

    2017-05-05

    Waiting times for hospital appointments, treatment and/or surgery have become a major political and health service problem, leading to national maximum waiting times and policies to reduce waiting times. Quantitative studies have documented waiting times for various types of surgery and longer waiting times in public vs private hospitals. However, very little qualitative research has explored patient experiences of waiting, how this compares between public and private hospitals, and the implications for trust in hospitals and healthcare professionals. The aim of this paper is to provide a deep understanding of the impact of waiting times on patient trust in public and private hospitals. A qualitative study in South Australia, including 36 in-depth interviews (18 from public and 18 from private hospitals). Data collection occurred in 2012-13, and data were analysed using pre-coding, followed by conceptual and theoretical categorisation. Participants differentiated between experiences of 'waiting for' (e.g. for specialist appointments and surgery) and 'waiting in' (e.g. in emergency departments and outpatient clinics) public and private hospitals. Whilst 'waiting for' public hospitals was longer than private hospitals, this was often justified and accepted by public patients (e.g. due to reduced government funding), therefore it did not lead to distrust of public hospitals. Private patients had shorter 'waiting for' hospital services, increasing their trust in private hospitals and distrust of public hospitals. Public patients also recounted many experiences of longer 'waiting in' public hospitals, leading to frustration and anxiety, although they rarely blamed or distrusted the doctors or nurses, instead blaming an underfunded system and over-worked staff. Doctors and nurses were seen to be doing their best, and therefore trustworthy. Although public patients experienced longer 'waiting for' and 'waiting in' public hospitals, it did not lead to widespread distrust

  9. Chances of late surgery in relation to length of wait lists

    Directory of Open Access Journals (Sweden)

    Levy Adrian R

    2005-09-01

    Full Text Available Abstract Background The proportion of patients who undergo surgery within a clinically safe time is an important performance indicator in health systems that use wait lists to manage access to care. However, little is known about chances of on-time surgery according to variations in existing demand. We sought to determine what proportion of patients have had late coronary bypass surgery after registration on wait lists of different size in a network of hospitals with uniform standards for timing of surgery. Methods Using records from a population-based registry, we studied wait-list times prospectively collected in a cohort of patients registered on wait lists for coronary artery bypass grafting procedures. We compared the number of weeks from registration to surgery against target access times established for three urgency groups. The chances of undergoing surgery within target time have been evaluated in relation to wait-list size at registration and the number of surgeries performed without registration on a wait list. Results In 1991–2001, two in three patients were at risk of late surgery when registered on wait lists for isolated coronary bypass procedures in British Columbia, Canada. Although urgent patients had never seen a wait list with clearance time exceeding one week, the odds of on-time surgery were reduced by 25%, odds ratio [OR] = 0.75 (95% confidence interval [CI] 0.65–0.87 for every additional operation performed without registration on a list. When the wait list at registration required a clearance time of over one month, semi-urgent patients had 51% lower odds of on-time surgery as compared to lists with clearance time less than one week, OR = 0.49 (95%CI 0.41–0.60, after adjustment for age, sex, comorbidity, calendar period, hospital and week on the list. In the non-urgent group, the odds were 69% lower, OR = 0.31 (95%CI 0.20–0.47. Every time an operation in the same hospital was performed without registration on a

  10. Ramsey waits: allocating public health service resources when there is rationing by waiting.

    Science.gov (United States)

    Gravelle, Hugh; Siciliani, Luigi

    2008-09-01

    The optimal allocation of a public health care budget across treatments must take account of the way in which care is rationed within treatments since this will affect their marginal value. We investigate the optimal allocation rules for public health care systems where user charges are fixed and care is rationed by waiting. The optimal waiting time is higher for treatments with demands more elastic to waiting time, higher costs, lower charges, smaller marginal welfare loss from waiting by treated patients, and smaller marginal welfare losses from under-consumption of care. The results hold for a wide range of welfarist and non-welfarist objective functions and for systems in which there is also a private health care sector. They imply that allocation rules based purely on cost effectiveness ratios are suboptimal because they assume that there is no rationing within treatments.

  11. Real-time method of powder diffraction for non-periodic and nearly periodic materials

    International Nuclear Information System (INIS)

    Egami, T.; Toby, B.H.; Dmowski, T.W.; Jorgensen, J.D.

    1989-12-01

    The use of high-energy neutrons from pulsed or hot sources allows the method of atomic pair distribution analysis to be applied to the structural determination of crystalline as well as amorphous solids. This method complements the standard crystallographic methods in studying non-periodic aspects of solids with or without long range order. 14 refs., 3 figs

  12. Controlling mixing and segregation in time periodic granular flows

    Science.gov (United States)

    Bhattacharya, Tathagata

    of realistic results and is used as a means of validating the model against available experimental data. The tuned model is then used to find the critical chute length for segregation based on the hypothesis that segregation can be thwarted if the particle flow is inverted at a rate above a critical forcing frequency. The critical frequency, fcrit, is inversely proportional to the characteristic time of segregation, ts. Mixing is observed instead of segregation when the chute length L Rate-based separation processes hold promise as both more environmentally benign as well as less energy intensive when compared to conventional particle separations technologies such as vibrating screens or flotation methods. This approach is based on differences in the kinetic properties of the components of a mixture, such as the velocity of migration or diffusivity. In this portion of the work, two examples of novel rate-based separation devices are demonstrated. The first example involves the study of the dynamics of gravity-driven particles through an array of obstacles. Both discrete element (DEM) simulations and experiments are used to augment the understanding of this device. Dissipative collisions (both between the particles themselves and with the obstacles) give rise to a diffusive motion of particles perpendicular to the flow direction and the differences in diffusion lengths are exploited to separate the particles. The second example employs DEM to analyze a ratchet mechanism where a current of particles can be produced in a direction perpendicular to the energy input. In this setup, a vibrating saw-toothed base is employed to induce different mobility for different types of particles. The effect of operating conditions and design parameters on the separation efficiency are discussed. Keywords: granular flow, particle, mixing, segregation, discrete element method, particle dynamics, tumbler, chute, periodic flow inversion, collisional flow, rate-based separation, ratchet

  13. Long-time correlations of periodic, area-preserving maps

    International Nuclear Information System (INIS)

    Meiss, J.D.; Cary, J.R.; Grebogi, C.; Crawford, J.D.; Kaufman, A.N.; Abarbanel, H.D.I.

    1982-04-01

    A simple analytical decay law for correlation functions of periodic, area-preserving maps is obtained. This law is compared with numerical experiments on the standard map. The agreement between experiment and theory is good when islands are absent, but poor when islands are present. When islands are present, the correlations have a long, slowly decaying tail

  14. Logic Model Checking of Time-Periodic Real-Time Systems

    Science.gov (United States)

    Florian, Mihai; Gamble, Ed; Holzmann, Gerard

    2012-01-01

    In this paper we report on the work we performed to extend the logic model checker SPIN with built-in support for the verification of periodic, real-time embedded software systems, as commonly used in aircraft, automobiles, and spacecraft. We first extended the SPIN verification algorithms to model priority based scheduling policies. Next, we added a library to support the modeling of periodic tasks. This library was used in a recent application of the SPIN model checker to verify the engine control software of an automobile, to study the feasibility of software triggers for unintended acceleration events.

  15. Periodic capacity management under a lead-time performance constraint

    NARCIS (Netherlands)

    Büyükkaramikli, N.C.; Bertrand, J.W.M.; Ooijen, van H.P.G.

    2013-01-01

    In this paper, we study a production system that operates under a lead-time performance constraint which guarantees the completion of an order before a pre-determined lead-time with a certain probability. The demand arrival times and the service requirements for the orders are random. To reduce the

  16. On a Batch Arrival Queuing System Equipped with a Stand-by Server during Vacation Periods or the Repairs Times of the Main Server

    Directory of Open Access Journals (Sweden)

    Rehab F. Khalaf

    2011-01-01

    Full Text Available We study a queuing system which is equipped with a stand-by server in addition to the main server. The stand-by server provides service to customers only during the period of absence of the main server when either the main server is on a vacation or it is in the state of repairs due to a sudden failure from time to time. The service times, vacation times, and repair times are assumed to follow general arbitrary distributions while the stand-by service times follow exponential distribution. Supplementary variables technique has been used to obtain steady state results in explicit and closed form in terms of the probability generating functions for the number of customers in the queue, the average number of customers, and the average waiting time in the queue while the MathCad software has been used to illustrate the numerical results in this work.

  17. Impact of visual art on patient behavior in the emergency department waiting room.

    Science.gov (United States)

    Nanda, Upali; Chanaud, Cheryl; Nelson, Michael; Zhu, Xi; Bajema, Robyn; Jansen, Ben H

    2012-07-01

    Wait times have been reported to be one of the most important concerns for people visiting emergency departments (EDs). Affective states significantly impact perception of wait time. There is substantial evidence that art depicting nature reduces stress levels and anxiety, thus potentially impacting the waiting experience. To analyze the effect of visual art depicting nature (still and video) on patients' and visitors' behavior in the ED. A pre-post research design was implemented using systematic behavioral observation of patients and visitors in the ED waiting rooms of two hospitals over a period of 4 months. Thirty hours of data were collected before and after new still and video art was installed at each site. Significant reduction in restlessness, noise level, and people staring at other people in the room was found at both sites. A significant decrease in the number of queries made at the front desk and a significant increase in social interaction were found at one of the sites. Visual art has positive effects on the ED waiting experience. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. Time-delayed feedback technique for suppressing instabilities in time-periodic flow

    Science.gov (United States)

    Shaabani-Ardali, Léopold; Sipp, Denis; Lesshafft, Lutz

    2017-11-01

    A numerical method is presented that allows to compute time-periodic flow states, even in the presence of hydrodynamic instabilities. The method is based on filtering nonharmonic components by way of delayed feedback control, as introduced by Pyragas [Phys. Lett. A 170, 421 (1992), 10.1016/0375-9601(92)90745-8]. Its use in flow problems is demonstrated here for the case of a periodically forced laminar jet, subject to a subharmonic instability that gives rise to vortex pairing. The optimal choice of the filter gain, which is a free parameter in the stabilization procedure, is investigated in the context of a low-dimensional model problem, and it is shown that this model predicts well the filter performance in the high-dimensional flow system. Vortex pairing in the jet is efficiently suppressed, so that the unstable periodic flow state in response to harmonic forcing is accurately retrieved. The procedure is straightforward to implement inside any standard flow solver. Memory requirements for the delayed feedback control can be significantly reduced by means of time interpolation between checkpoints. Finally, the method is extended for the treatment of periodic problems where the frequency is not known a priori. This procedure is demonstrated for a three-dimensional cubic lid-driven cavity in supercritical conditions.

  19. Protocol to Exploit Waiting Resources for UASNs

    Directory of Open Access Journals (Sweden)

    Li-Ling Hung

    2016-03-01

    Full Text Available The transmission speed of acoustic waves in water is much slower than that of radio waves in terrestrial wireless sensor networks. Thus, the propagation delay in underwater acoustic sensor networks (UASN is much greater. Longer propagation delay leads to complicated communication and collision problems. To solve collision problems, some studies have proposed waiting mechanisms; however, long waiting mechanisms result in low bandwidth utilization. To improve throughput, this study proposes a slotted medium access control protocol to enhance bandwidth utilization in UASNs. The proposed mechanism increases communication by exploiting temporal and spatial resources that are typically idle in order to protect communication against interference. By reducing wait time, network performance and energy consumption can be improved. A performance evaluation demonstrates that when the data packets are large or sensor deployment is dense, the energy consumption of proposed protocol is less than that of existing protocols as well as the throughput is higher than that of existing protocols.

  20. Using travel times to simulate multi-dimensional bioreactive transport in time-periodic flows.

    Science.gov (United States)

    Sanz-Prat, Alicia; Lu, Chuanhe; Finkel, Michael; Cirpka, Olaf A

    2016-04-01

    In travel-time models, the spatially explicit description of reactive transport is replaced by associating reactive-species concentrations with the travel time or groundwater age at all locations. These models have been shown adequate for reactive transport in river-bank filtration under steady-state flow conditions. Dynamic hydrological conditions, however, can lead to fluctuations of infiltration velocities, putting the validity of travel-time models into question. In transient flow, the local travel-time distributions change with time. We show that a modified version of travel-time based reactive transport models is valid if only the magnitude of the velocity fluctuates, whereas its spatial orientation remains constant. We simulate nonlinear, one-dimensional, bioreactive transport involving oxygen, nitrate, dissolved organic carbon, aerobic and denitrifying bacteria, considering periodic fluctuations of velocity. These fluctuations make the bioreactive system pulsate: The aerobic zone decreases at times of low velocity and increases at those of high velocity. For the case of diurnal fluctuations, the biomass concentrations cannot follow the hydrological fluctuations and a transition zone containing both aerobic and obligatory denitrifying bacteria is established, whereas a clear separation of the two types of bacteria prevails in the case of seasonal velocity fluctuations. We map the 1-D results to a heterogeneous, two-dimensional domain by means of the mean groundwater age for steady-state flow in both domains. The mapped results are compared to simulation results of spatially explicit, two-dimensional, advective-dispersive-bioreactive transport subject to the same relative fluctuations of velocity as in the one-dimensional model. The agreement between the mapped 1-D and the explicit 2-D results is excellent. We conclude that travel-time models of nonlinear bioreactive transport are adequate in systems of time-periodic flow if the flow direction does not change

  1. Predictability of Landslide Timing From Quasi-Periodic Precursory Earthquakes

    Science.gov (United States)

    Bell, Andrew F.

    2018-02-01

    Accelerating rates of geophysical signals are observed before a range of material failure phenomena. They provide insights into the physical processes controlling failure and the basis for failure forecasts. However, examples of accelerating seismicity before landslides are rare, and their behavior and forecasting potential are largely unknown. Here I use a Bayesian methodology to apply a novel gamma point process model to investigate a sequence of quasiperiodic repeating earthquakes preceding a large landslide at Nuugaatsiaq in Greenland in June 2017. The evolution in earthquake rate is best explained by an inverse power law increase with time toward failure, as predicted by material failure theory. However, the commonly accepted power law exponent value of 1.0 is inconsistent with the data. Instead, the mean posterior value of 0.71 indicates a particularly rapid acceleration toward failure and suggests that only relatively short warning times may be possible for similar landslides in future.

  2. Network Organization Unfolds over Time during Periods of Anxious Anticipation

    OpenAIRE

    McMenamin, Brenton W.; Langeslag, Sandra J.E.; Sirbu, Mihai; Padmala, Srikanth; Pessoa, Luiz

    2014-01-01

    Entering a state of anxious anticipation triggers widespread changes across large-scale networks in the brain. The temporal aspects of this transition into an anxious state are poorly understood. To address this question, an instructed threat of shock paradigm was used while recording functional MRI in humans to measure how activation and functional connectivity change over time across the salience, executive, and task-negative networks and how they interact with key regions implicated in emo...

  3. The boarding experience from the patient perspective: the wait.

    Science.gov (United States)

    Liu, Shan; Milne, Leslie; Yun, Brian; Walsh, Kathleen

    2015-11-01

    We sought to better understand the experience of being a boarder patient. We conducted a qualitative study between March and August 2012 to examine the experience of boarding in an urban, teaching hospital emergency department (ED). We included boarder patients and selected patients based on a convenience sample. Interviews were semistructured, consisting of eight main open-ended questions. Interviews were transcribed; codes were generated and then organised into categorises and subsequently into one theme. We concluded analysis when we achieved thematic saturation. Our institutional review board approved this study. Our final sample included 18 patients. The average age was 62.3 years. Patients characterised waiting as central to their experience as a boarder patient. One patient stated, "Well if you have to wait for a bed you have to wait for a bed, it's terrible." Three categories exemplified this waiting experience: (1) there was often lack of communication; (2) patients experienced frustration during this waiting period; and yet (3) patients often differentiated the experience of waiting from the care they were receiving. Being a boarder patient was characterised as a waiting experience associated with poor communication and frustration. However, patients may still differentiate their feelings towards the wait from those towards the medical care they are receiving. Our data add more reason to eradicate the practice of ED boarding. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  4. No-Wait Flexible Flow Shop Scheduling with Due Windows

    Directory of Open Access Journals (Sweden)

    Rong-Hwa Huang

    2015-01-01

    Full Text Available To improve capacity and reduce processing time, the flow shop with multiprocessors (FSMP system is commonly used in glass, steel, and semiconductor production. No-wait FSMP is a modern production system that responds to periods when zero work is required in process production. The production process must be continuous and uninterrupted. Setup time must also be considered. Just-in-time (JIT production is very popular in industry, and timely delivery is important to customer satisfaction. Therefore, it is essential to consider the time window constraint, which is also very complex. This study focuses on a no-wait FSMP problem with time window constraint. An improved ant colony optimization (ACO, known as ant colony optimization with flexible update (ACOFU, is developed to solve the problem. The results demonstrate that ACOFU is more effective and robust than ACO when applied to small-scale problems. ACOFU has superior solution capacity and robustness when applied to large-scale problems. Therefore, this study concludes that the proposed algorithm ACOFU performs excellently when applied to the scheduling problem discussed in this study.

  5. [Obesity and complementary feeding time: a period at risk].

    Science.gov (United States)

    Vidailhet, M

    2010-12-01

    Relation between rapid growth during the first months of life and secondary risk of excessive adiposity is well demonstrated. Many works have indicated a birth feeding effect on weight gain during the first year of life and a protective effect towards later childhood and adult obesity. However all these studies are observational and several works denied this protective effect. Concerning complementary feeding, 3 interventional, randomized, studies achieved between 4 and 6 months of age, showed a good regulation of caloric intake and no weight gain modification due to complementary foods. Most of others studies are observational and don't show any relation between time of introduction of complementary foods and later fat mass. However 3 recent studies indicate, respectively at 7, 10 and 42 years of age, an increased adiposity, suggesting the possibility of a programmed excessive fat gain induced by an early complementary foods introduction. Very few studies have evaluated, besides the time of weaning, the kind, quantity and caloric density of foods used as complements, whereas other recent studies show the importance of appetite differences since the first months of life and the importance of genetic influence on these variations. Others works have emphasized the possible role of an excessive protein intake during the first 2 years of life. So, it appears that it may be necessary to pay attention not only on the date, but also on the kind and quantity of complementary foods, particularly in infants at risk for obesity, because of parental obesity, rapid weight growth or an excessive appetite. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

  6. Urgency coding as a dynamic tool in management of waiting lists for psychogeriatric nursing home care in The Netherlands

    NARCIS (Netherlands)

    Meiland, F. J. M.; Danse, J. A. C.; Wendte, J. F.; Gunning-Schepers, L. J.; Klazinga, N. S.

    2002-01-01

    Criteria are used to prioritise patients on waiting lists for health care services. This is also true for waiting lists for admission to psychogeriatric nursing homes. A patient's position on these latter waiting lists is determined by (changes in) urgency and waiting time. The present article

  7. Using probability of drug use as independent variable in a register-based pharmacoepidemiological cause-effect study-An application of the reverse waiting time distribution

    DEFF Research Database (Denmark)

    Hallas, Jesper; Pottegård, Anton; Støvring, Henrik

    2017-01-01

    generated adjusted ORs in the upper range (4.37-4.75) while at the same time having the most narrow confidence intervals (ratio between upper and lower confidence limit, 1.46-1.50). Some ORs generated by conventional measures were higher than the probabilistic ORs, but only when the assumed period of intake......BACKGROUND: In register-based pharmacoepidemiological studies, each day of follow-up is usually categorized either as exposed or unexposed. However, there is an underlying continuous probability of exposure, and by insisting on a dichotomy, researchers unwillingly force a nondifferential...... misclassification into their analyses. We have recently developed a model whereby probability of exposure can be modeled, and we tested this on an empirical case of nonsteroidal anti-inflammatory drug (NSAID)-induced upper gastrointestinal bleeding (UGIB). METHODS: We used a case-controls data set, consisting...

  8. Transient solution of an M/M/1 vacation queue with a waiting server and impatient customers

    Directory of Open Access Journals (Sweden)

    Sherif I. Ammar

    2017-07-01

    Full Text Available Recently, Ammar [1] has discussed the transient behavior of a multiple vacations queue with impatient customers. In this paper, a similar technique is used to derive a new elegant explicit solution for an M/M/1 vacation queue with impatient customers and a waiting server, where the server is allowed to take a vacation whenever the system is empty after waiting for a random period of time. If the server does not return from the vacation before the expiry of the customer impatience time, the customer abandons the system forever. Moreover, the formulas of mean and variance expressed in terms of the obtained possibilities for this model.

  9. The association between waiting for psychological therapy and therapy outcomes as measured by the CORE-OM.

    Science.gov (United States)

    Beck, Alison; Burdett, Mark; Lewis, Helen

    2015-06-01

    To investigate the impact of waiting for psychological therapy on client well-being as measured by the Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM) global distress (GD) score. Global distress scores were retrieved for all clients referred for psychological therapy in a secondary care mental health service between November 2006 and May 2013 and who had completed a CORE-OM at assessment and first session. GD scores for a subgroup of 103 clients who had completed a CORE-OM during the last therapy session were also reviewed. The study sample experienced a median wait of 41.14 weeks between assessment and first session. The relationship between wait time from referral acceptance to assessment, and assessment GD score was not significant. During the period between assessment and first session no significant difference in GD score was observed. Nevertheless 29.1% of the sample experienced reliable change; 16.0% of clients reliably improved and 13.1% reliably deteriorated whilst waiting for therapy. Demographic factors were not found to have a significant effect on the change in GD score between assessment and first session. Waiting time was associated with post-therapy outcomes but not to a degree which was meaningful. The majority of individuals (54.4%), regardless of whether they improved or deteriorated whilst waiting for therapy, showed reliable improvement at end of therapy as measured by the CORE-OM. The majority of GD scores remained stable while waiting for therapy; however, 29.1% of secondary care clients experienced either reliable improvement or deterioration. Irrespective of whether they improved, deteriorated or remained unchanged whilst waiting for therapy, most individuals who had a complete end of therapy assessment showed reliable improvements following therapy. There was no significant difference in GD score between assessment and first session recordings. A proportion of clients (29.1%) showed reliable change, either improvement or

  10. Enhanced diffusion with abnormal temperature dependence in underdamped space-periodic systems subject to time-periodic driving

    Science.gov (United States)

    Marchenko, I. G.; Marchenko, I. I.; Zhiglo, A. V.

    2018-01-01

    We present a study of the diffusion enhancement of underdamped Brownian particles in a one-dimensional symmetric space-periodic potential due to external symmetric time-periodic driving with zero mean. We show that the diffusivity can be enhanced by many orders of magnitude at an appropriate choice of the driving amplitude and frequency. The diffusivity demonstrates abnormal (decreasing) temperature dependence at the driving amplitudes exceeding a certain value. At any fixed driving frequency Ω normal temperature dependence of the diffusivity is restored at low enough temperatures, T oscillation frequency at the potential minimum, the diffusivity is shown to decrease with Ω according to a power law, with the exponent related to the transient superdiffusion exponent. This behavior is found similar for the cases of sinusoidal in time and piecewise constant periodic ("square") driving.

  11. [Study of the labor market for dentists who recieved Norwegian authorization during 1972-1975. I. Waiting time and alternative employment before the 1st relevant job].

    Science.gov (United States)

    Haugejorden, O

    1977-07-01

    The purpose of the investigation was to monitor changes in the labour market situation for dentists who received authorization to practise dentistry in Norway during the years 1972-1975. Data was collected by postal questionnaire during April/May of the year following authorization, except for the 1972 cohort, which was contacted the second year after authorization. A 92-95 per cent response rate was achieved using one follow-up (Table 1). The percentage of respondents who waited 8 weeks or more to acquire a job in dentistry increased from 15 for those authorized in 1972 to 36 for the 1975 group (Table 3). The proportion of dentists who took paid employment other than dentistry, increased from just over 3 per cent for the 1973 to 14 per cent for the 1975 cohort (Table 4). This development has occured despite a decrease in the number of dentists receiving authorization each year and has resulted in a limited emigration of dentists. It is suggested that the favourable supply of dentists in relation to existing demand for dental services presents an ideal opportunity for attempting to solve dental health problems which have received inadequate attention in the past.

  12. How Tolerable is Delay? Consumers' Evaluations of Internet Web Sites After Waiting

    NARCIS (Netherlands)

    Dellaert, B.G.C.; Kahn, B.

    1998-01-01

    How consumers’ waiting times affect their retrospective evaluations of Internet Web Sites is investigated in four computer-based experiments. Results show that waiting can but does not always negatively affect evaluations of Web Sites. Results also show that the potential negative effects of waiting

  13. Implementing the access and waiting time standard for early intervention in psychosis in the United Kingdom: An evaluation of referrals and post-assessment outcomes over the first year of operation.

    Science.gov (United States)

    Adamson, Vidyah; Barrass, Emma; McConville, Stephen; Irikok, Chantelle; Taylor, Kim; Pitt, Steve; Van Duyn, Rob; Bennett, Susan; Jackson, Lisa; Carroll, Jon; Andrews, Mark; Parker, Ann; Wright, Caroline; Greathead, Katie; Price, David

    2018-03-26

    Improving timely access to evidence-based treatment for people aged 14-65 years experiencing a first episode psychosis (FEP) or an at-risk mental state (ARMS) for psychosis is a national priority within the United Kingdom. An early intervention in psychosis (EIP) access and waiting time standard has been set which has extended the age range and acceptance criteria for services. This descriptive evaluation reports upon the referrals and access to treatment times within an EIP service over the first year of operating in line with the access and waiting time standard. Patient pathways and post-assessment status are also described. The service received 406 referrals, of which 88% (n = 357) were assessed. The mean length of time to treatment was 1.5 weeks, with 88% being seen within 2 weeks. Of those who engaged in an assessment, 34% (n = 138) were identified as ARMS cases and 30% (n = 123) were identified as FEP. Over 35 year olds accounted for 22% (n = 80) of the total accepted cases. The findings indicate clinical and operational issues, which will need careful consideration in the future planning of services. The high number of ARMS cases highlights the importance of clear treatment pathways and targeted interventions and may suggest a need to commission distinct ARMS services. The number of people who met the extended age and service acceptance criteria may suggest a need to adapt or redesign clinical services to meet the age-specific needs of over 35 year olds and those with an ARMS. It is unclear how changes to the remit of EIP services will impact upon future clinical outcomes. © 2018 John Wiley & Sons Australia, Ltd.

  14. Natural convection in square enclosure induced by inner circular cylinder with time-periodic pulsating temperature

    KAUST Repository

    Huang, Zhu; Zhang, Wei; Xi, Guang

    2015-01-01

    The periodic unsteady natural convection flow and heat transfer in a square enclosure containing a concentric circular cylinder is numerically studied. The temperature of the inner circular cylinder fluctuates periodically with time at higher

  15. Finite-Difference Time-Domain Simulation of Light Propagation in 2D Periodic and Quasi-Periodic Photonic Structures

    Directory of Open Access Journals (Sweden)

    N. Dadashzadeh

    2013-09-01

    Full Text Available Ultra-short pulse is a promising technology for achieving ultra-high data rate transmission which is required to follow the increased demand of data transport over an optical communication system. Therefore, the propagation of such type of pulses and the effects that it may suffer during its transmission through an optical waveguide has received a great deal of attention in the recent years. We provide an overview of recent theoretical developments in a numerical modeling of Maxwell's equations to analyze the propagation of short laser pulses in photonic structures. The process of short light pulse propagation through 2D periodic and quasi-periodic photonic structures is simulated based on Finite-Difference Time-Domain calculations of Maxwell’s equations.

  16. Waiting narratives of lung transplant candidates.

    Science.gov (United States)

    Yelle, Maria T; Stevens, Patricia E; Lanuza, Dorothy M

    2013-01-01

    Before 2005, time accrued on the lung transplant waiting list counted towards who was next in line for a donor lung. Then in 2005 the lung allocation scoring system was implemented, which meant the higher the illness severity scores, the higher the priority on the transplant list. Little is known of the lung transplant candidates who were listed before 2005 and were caught in the transition when the lung allocation scoring system was implemented. A narrative analysis was conducted to explore the illness narratives of seven lung transplant candidates between 2006 and 2007. Arthur Kleinman's concept of illness narratives was used as a conceptual framework for this study to give voice to the illness narratives of lung transplant candidates. Results of this study illustrate that lung transplant candidates expressed a need to tell their personal story of waiting and to be heard. Recommendation from this study calls for healthcare providers to create the time to enable illness narratives of the suffering of waiting to be told. Narrative skills of listening to stories of emotional suffering would enhance how healthcare providers could attend to patients' stories and hear what is most meaningful in their lives.

  17. Waiting Narratives of Lung Transplant Candidates

    Directory of Open Access Journals (Sweden)

    Maria T. Yelle

    2013-01-01

    Full Text Available Before 2005, time accrued on the lung transplant waiting list counted towards who was next in line for a donor lung. Then in 2005 the lung allocation scoring system was implemented, which meant the higher the illness severity scores, the higher the priority on the transplant list. Little is known of the lung transplant candidates who were listed before 2005 and were caught in the transition when the lung allocation scoring system was implemented. A narrative analysis was conducted to explore the illness narratives of seven lung transplant candidates between 2006 and 2007. Arthur Kleinman’s concept of illness narratives was used as a conceptual framework for this study to give voice to the illness narratives of lung transplant candidates. Results of this study illustrate that lung transplant candidates expressed a need to tell their personal story of waiting and to be heard. Recommendation from this study calls for healthcare providers to create the time to enable illness narratives of the suffering of waiting to be told. Narrative skills of listening to stories of emotional suffering would enhance how healthcare providers could attend to patients’ stories and hear what is most meaningful in their lives.

  18. Patients’ Attitude towards Travelling For Breast Services versus Waiting Longer For Local Services

    LENUS (Irish Health Repository)

    Abd Elwahab, S

    2018-05-01

    Geographical access is a cornerstone of health care provision. However, prolonged waiting for breast clinic appointments in local services results in delayed diagnosis and excessive anxiety for patients. In this study, we present a patient satisfaction survey results of an initiative to offer out-patient clinic appointments for non-urgent patients referred to the breast unit in Letterkenny General Hospital (LGH), Ireland, and exceeded the recommended waiting period of 12 weeks. These patients were offered appointment in University Hospital Galway (UCHG), which is an average travel time of about 3.5-4.5 hours away from LGH. 163 patients out of 336 (48.5%) patients actively waiting more than 12 weeks for appointments in LGH accepted alternative appointments in UCHG. Despite the long travel distance for these patients, 100% of them reported high satisfaction and 97.3% said they would accept further UCHG appointments if a similar situation of prolonged waiting in LGH arises. None of these patients were diagnosed with cancer, and only one had a benign lumpectomy. This study showed that if offered alternative appointments, just under half of the patients would accept. The initiative provides a feasible solution for long waiters, and the survey shows that patients’ satisfaction remains high despite long travel.

  19. Structure and dating errors in the geologic time scale and periodicity in mass extinctions

    Science.gov (United States)

    Stothers, Richard B.

    1989-01-01

    Structure in the geologic time scale reflects a partly paleontological origin. As a result, ages of Cenozoic and Mesozoic stage boundaries exhibit a weak 28-Myr periodicity that is similar to the strong 26-Myr periodicity detected in mass extinctions of marine life by Raup and Sepkoski. Radiometric dating errors in the geologic time scale, to which the mass extinctions are stratigraphically tied, do not necessarily lessen the likelihood of a significant periodicity in mass extinctions, but do spread the acceptable values of the period over the range 25-27 Myr for the Harland et al. time scale or 25-30 Myr for the DNAG time scale. If the Odin time scale is adopted, acceptable periods fall between 24 and 33 Myr, but are not robust against dating errors. Some indirect evidence from independently-dated flood-basalt volcanic horizons tends to favor the Odin time scale.

  20. Time-periodic solution of a 2D fourth-order nonlinear parabolic ...

    Indian Academy of Sciences (India)

    appropriate function space for the initial boundary value problem. ... time discretizations which allow much larger time steps than those of a standard implicit– explicit approach. ... set of ω-periodic X-valued measurable functions on R such that.

  1. Smith predictor-based multiple periodic disturbance compensation for long dead-time processes

    Science.gov (United States)

    Tan, Fang; Li, Han-Xiong; Shen, Ping

    2018-05-01

    Many disturbance rejection methods have been proposed for processes with dead-time, while these existing methods may not work well under multiple periodic disturbances. In this paper, a multiple periodic disturbance rejection is proposed under the Smith predictor configuration for processes with long dead-time. One feedback loop is added to compensate periodic disturbance while retaining the advantage of the Smith predictor. With information of the disturbance spectrum, the added feedback loop can remove multiple periodic disturbances effectively. The robust stability can be easily maintained through the rigorous analysis. Finally, simulation examples demonstrate the effectiveness and robustness of the proposed method for processes with long dead-time.

  2. Analysis of bluetooth and wi-fi technology to measure wait times of personal vehicles at Arizona-Mexico ports of entry.

    Science.gov (United States)

    2015-11-01

    Robust travel time data collection is possible using Bluetooth or Wi-Fi technology that : matches anonymous MAC addresses from discoverable electronic devices (e.g., smart phones) : to determine travel time along a roadway segment. Several hundred...

  3. Learning to wait: A laboratory investigation

    Science.gov (United States)

    Oprea, R.; Friedman, D.; Anderson, S.T.

    2009-01-01

    Human subjects decide when to sink a fixed cost C to seize an irreversible investment opportunity whose value V is governed by Brownian motion. The optimal policy is to invest when V first crosses a threshold V* = (1 + w*) C, where the wait option premium w* depends on drift, volatility, and expiration hazard parameters. Subjects in the Low w* treatment on average invest at values quite close to optimum. Subjects in the two Medium and the High w* treatments invested at values below optimum, but with the predicted ordering, and values approached the optimum by the last block of 20 periods. ?? 2009 The Review of Economic Studies Limited.

  4. 12 CFR 516.10 - How does OTS compute time periods under this part?

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false How does OTS compute time periods under this part? 516.10 Section 516.10 Banks and Banking OFFICE OF THRIFT SUPERVISION, DEPARTMENT OF THE TREASURY APPLICATION PROCESSING PROCEDURES § 516.10 How does OTS compute time periods under this part? In computing...

  5. 19 CFR 351.524 - Allocation of benefit to a particular time period.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Allocation of benefit to a particular time period. 351.524 Section 351.524 Customs Duties INTERNATIONAL TRADE ADMINISTRATION, DEPARTMENT OF COMMERCE... Allocation of benefit to a particular time period. Unless otherwise specified in §§ 351.504-351.523, the...

  6. 17 CFR 260.7a-24 - Words relating to periods of time in the past.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Words relating to periods of time in the past. 260.7a-24 Section 260.7a-24 Commodity and Securities Exchanges SECURITIES AND... Requirements As to Contents § 260.7a-24 Words relating to periods of time in the past. Unless the context...

  7. The Impact of Patient-to-Patient Interaction in Health Facility Waiting Rooms on Their Perception of Health Professionals.

    Science.gov (United States)

    Willis, William Kent; Ozturk, Ahmet Ozzie; Chandra, Ashish

    2015-01-01

    Patients have to wait in waiting rooms prior to seeing the physician. But there are few studies that demonstrate what they are actually doing in the waiting room. This exploratory study was designed to investigate the types of discussions that patients in the waiting room typically engage in with other patients and how the conversations affected their opinion on general reputation of the clinic, injections/blocks as treatment procedures, waiting time, time spent with the caregiver, overall patient satisfaction, and the pain medication usage policy. The study demonstrates that patient interaction in the waiting room has a positive effect on patient opinion of the pain clinic and the caregivers.

  8. Modal Vibration Control in Periodic Time-Varying Structures with Focus on Rotor Blade Systems

    DEFF Research Database (Denmark)

    Christensen, Rene Hardam; Santos, Ilmar

    2004-01-01

    of active modal controllers. The main aim is to reduce vibrations in periodic time-varying structures. Special emphasis is given to vibration control of coupled bladed rotor systems. A state feedback modal control law is developed based on modal analysis in periodic time-varying structures. The first step...... in the procedure is a transformation of the model into a time-invariant modal form by applying the modal matrices, which are also periodic time-variant. Due to coupled rotor and blade motions complex vibration modes occur in the modal transformed state space model. This implies that the modal transformed model...

  9. Scattering analysis of periodic structures using finite-difference time-domain

    CERN Document Server

    ElMahgoub, Khaled; Elsherbeni, Atef Z

    2012-01-01

    Periodic structures are of great importance in electromagnetics due to their wide range of applications such as frequency selective surfaces (FSS), electromagnetic band gap (EBG) structures, periodic absorbers, meta-materials, and many others. The aim of this book is to develop efficient computational algorithms to analyze the scattering properties of various electromagnetic periodic structures using the finite-difference time-domain periodic boundary condition (FDTD/PBC) method. A new FDTD/PBC-based algorithm is introduced to analyze general skewed grid periodic structures while another algor

  10. Brazil well worth the wait

    Energy Technology Data Exchange (ETDEWEB)

    Duey, R.

    1999-11-01

    Oil companies weren't the only ones waiting for Brazil to make up its mind about privatizing its oil and gas industry. Seismic firms are flocking to the area in droves to work their spec magic. Exploratory activities in these large offshore blocks are described.

  11. The existence and global attractivity of almost periodic sequence solution of discrete-time neural networks

    International Nuclear Information System (INIS)

    Huang Zhenkun; Wang Xinghua; Gao Feng

    2006-01-01

    In this Letter, we discuss discrete-time analogue of a continuous-time cellular neural network. Sufficient conditions are obtained for the existence of a unique almost periodic sequence solution which is globally attractive. Our results demonstrate dynamics of the formulated discrete-time analogue as mathematical models for the continuous-time cellular neural network in almost periodic case. Finally, a computer simulation illustrates the suitability of our discrete-time analogue as numerical algorithms in simulating the continuous-time cellular neural network conveniently

  12. Waiting for the Payday?

    DEFF Research Database (Denmark)

    Arora, Ashish; Fosfuri, Andrea; Rønde, Thomas

    Most technology startups are set up for exit through acquisition by large corporations. In choosing when to sell, startups face a tradeoff. Early acquisitions reduce execution errors but later acquisitions improve the likelihood of finding a better match because there are fewer buyers in the early...... market as early acquisitions require costly absorptive capacity. Moreover, the decision of buyers to invest in absorptive capacity is related to the decision of startups on the timing of the exit sale. In this paper, we build a model to capture this complexity and the related tradeoffs. We find......, when the timing of exit is a tactical choice, i.e., startups can choose to go late after observing the early offers, there are too many early acquisitions and too much investment in absorptive capacity by incumbents....

  13. Period, epoch, and prediction errors of ephemerides from continuous sets of timing measurements

    Science.gov (United States)

    Deeg, H. J.

    2015-06-01

    Space missions such as Kepler and CoRoT have led to large numbers of eclipse or transit measurements in nearly continuous time series. This paper shows how to obtain the period error in such measurements from a basic linear least-squares fit, and how to correctly derive the timing error in the prediction of future transit or eclipse events. Assuming strict periodicity, a formula for the period error of these time series is derived, σP = σT (12 / (N3-N))1 / 2, where σP is the period error, σT the timing error of a single measurement, and N the number of measurements. Compared to the iterative method for period error estimation by Mighell & Plavchan (2013), this much simpler formula leads to smaller period errors, whose correctness has been verified through simulations. For the prediction of times of future periodic events, usual linear ephemeris were epoch errors are quoted for the first time measurement, are prone to an overestimation of the error of that prediction. This may be avoided by a correction for the duration of the time series. An alternative is the derivation of ephemerides whose reference epoch and epoch error are given for the centre of the time series. For long continuous or near-continuous time series whose acquisition is completed, such central epochs should be the preferred way for the quotation of linear ephemerides. While this work was motivated from the analysis of eclipse timing measures in space-based light curves, it should be applicable to any other problem with an uninterrupted sequence of discrete timings for which the determination of a zero point, of a constant period and of the associated errors is needed.

  14. Switched periodic systems in discrete time: stability and input-output norms

    Science.gov (United States)

    Bolzern, Paolo; Colaneri, Patrizio

    2013-07-01

    This paper deals with the analysis of stability and the characterisation of input-output norms for discrete-time periodic switched linear systems. Such systems consist of a network of time-periodic linear subsystems sharing the same state vector and an exogenous switching signal that triggers the jumps between the subsystems. The overall system exhibits a complex dynamic behaviour due to the interplay between the time periodicity of the subsystem parameters and the switching signal. Both arbitrary switching signals and signals satisfying a dwell-time constraint are considered. Linear matrix inequality conditions for stability and guaranteed H2 and H∞ performances are provided. The results heavily rely on the merge of the theory of linear periodic systems and recent developments on switched linear time-invariant systems.

  15. Waiting for a kidney transplant: the experience of patients with end-stage renal disease in South Korea.

    Science.gov (United States)

    Chong, Hye Jin; Kim, Hyun Kyung; Kim, Sung Reul; Lee, Sik

    2016-04-01

    To explore the experiences of Korean patients with end-stage renal disease awaiting kidney transplantation. The need for kidney transplantation has increased worldwide, while the number of kidney donors has not increased commensurately. This mismatch is a serious issue in South Korea. Prolonged waits for transplantation may cause physical and psychosocial issues and lead to poor outcomes. Nevertheless, the experience of waiting for kidney transplantation in South Korea has never been explored in depth. A qualitative descriptive design was used. The participants were eight patients diagnosed with end-stage renal disease on the waiting list for kidney transplantation in South Korea. Data were collected through individual in-depth interviews. All conversations during interviews were recorded and transcribed verbatim. Transcribed data were analysed using conventional content analysis. The experience of waiting for kidney transplantation consisted of six categories: (1) the light at the end of the tunnel, (2) being on call without any promise, (3) a tough tug of war between excitement and frustration, (4) doubts in the complexity, (5) A companion on the hard journey and (6) getting ready for D-day. Kidney transplantation candidates experience psychosocial difficulties and concerns while waiting for long periods of time without any assurance of resolution. Systematic education and psychosocial support from health care professionals and family members help patients get through what they describe as a difficult journey. Comprehensive management programs for kidney transplantation candidates are needed. Health care professionals need to recognise the psychosocial concerns of patients awaiting kidney transplantation. Clinicians should provide patients with information and support throughout the waiting period. © 2016 John Wiley & Sons Ltd.

  16. 46 CFR 167.60-5 - Period of time for which valid.

    Science.gov (United States)

    2010-10-01

    ... SCHOOL SHIPS Certificates of Inspection § 167.60-5 Period of time for which valid. A certificate of inspection for any period less than one year shall not be issued, but nothing herein shall be construed as preventing the revocation or suspension of a certificate of inspection in case such process is authorized by...

  17. Positive Almost Periodic Solutions for a Time-Varying Fishing Model with Delay

    Directory of Open Access Journals (Sweden)

    Xia Li

    2011-01-01

    Full Text Available This paper is concerned with a time-varying fishing model with delay. By means of the continuation theorem of coincidence degree theory, we prove that it has at least one positive almost periodic solution.

  18. Waiting list paradox: Danish cancer patients diagnosed fast have higher mortality after diagnosis

    DEFF Research Database (Denmark)

    Tørring, Marie Louise; Frydenberg, Morten; Hansen, Rikke Pilegaard

    on hospital discharge diagnoses for the 2004-2005 period, extracted from population-based healthcare databases in the former County of Aarhus, Denmark, and subsequently validated in the National Danish Cancer Registry. All patients with a first-time diagnosis of colon, rectal, lung, skin, breast, or prostate...... with longer diagnostic interval until the reference point of 30 days. For colon, rectal, skin, and breast cancer mortality seemed to increase with diagnostic interval longer than 30 days. The waiting list paradox is manifest in Denmark. We speculate that medical professionals organise the diagnostic pathway......Studies often show that cancer patients diagnosed more rapidly have higher mortality rates than patients with longer waits in the primary and secondary health care sector. Our aim was to examine whether this paradox is manifest in the Danish health care system. The study was based on data...

  19. Stability and periodicity of solutions for delay dynamic systems on time scales

    Directory of Open Access Journals (Sweden)

    Zhi-Qiang Zhu

    2014-04-01

    Full Text Available This article concerns the stability and periodicity of solutions to the delay dynamic system $$ x^{\\triangle}(t=A(t x(t + F(t, x(t, x(g(t+C(t $$ on a time scale. By the inequality technique for vectors, we obtain some stability criteria for the above system. Then, by using the Horn fixed point theorem, we present some conditions under which our system is asymptotically periodic and its periodic solution is unique. In particular, the periodic solution is positive under proper assumptions.

  20. Wuchereria bancrofti in Tanzania: microfilarial periodicity and effect of blood sampling time on microfilarial intensities

    DEFF Research Database (Denmark)

    Simonsen, Poul Erik; Niemann, L.; Meyrowitsch, Dan Wolf

    1997-01-01

    The circadian periodicity of Wuchereria bancrofti microfilarial (mf) intensities in peripheral blood was analysed in a group of infected individuals from an endemic community in north-eastern Tanzania. The mf density was quantified at two-hourly intervals for 24 hours. A clear nocturnal periodic...... of blood sampling before peak time is discussed, and the importance of taking sampling time into consideration when analysing data from epidemiological studies is emphasized. A simple method is devised which can be used to adjust for the influence of time on mf intensities, in studies where accurate...... information on mf intensities is necessary, and where it is impossible to obtain all samples at peak time....

  1. Existence of time-periodic weak solutions to the stochastic Navier-Stokes equations around a moving body

    International Nuclear Information System (INIS)

    Chen, Feng; Han, Yuecai

    2013-01-01

    The existence of time-periodic stochastic motions of an incompressible fluid is obtained. Here the fluid is subject to a time-periodic body force and an additional time-periodic stochastic force that is produced by a rigid body moves periodically stochastically with the same period in the fluid

  2. Existence of time-periodic weak solutions to the stochastic Navier-Stokes equations around a moving body

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Feng, E-mail: chenfengmath@163.com, E-mail: hanyc@jlu.edu.cn; Han, Yuecai, E-mail: chenfengmath@163.com, E-mail: hanyc@jlu.edu.cn [School of Mathematics, Jilin University, Changchun 130012 (China)

    2013-12-15

    The existence of time-periodic stochastic motions of an incompressible fluid is obtained. Here the fluid is subject to a time-periodic body force and an additional time-periodic stochastic force that is produced by a rigid body moves periodically stochastically with the same period in the fluid.

  3. The relationship between health locus of control, depression, and sociodemographic factors and amount of time breast cancer patients wait before seeking diagnosis and treatment.

    Science.gov (United States)

    Marijanović, Inga; Pavleković, Gordana; Buhovac, Teo; Martinac, Marko

    2017-09-01

    In the Federation of Bosnia and Herzegovina, the prevalence and incidence of breast cancer has been increasing, and the national programme of early prevention, administered locally, is sporadic and without quality assurance. While many factors may influence women's decision to adopt prevention-oriented behaviours regarding breast cancer, this study has emphasised the importance of sociodemographic factors, psychological factors and mental wellbeing. Participants in the study were all patients who, during one year, were admitted for the first time for diagnosis and treatment in the biggest Clinical hospitals of the Herzegovina-Neretva region Patients were divided into two groups based on their TNM classification: "early stage" and "late stage". Three instruments were used in this study: an individual questionnaire about demographic and socioeconomic characteristics of the woman, the Multidimensional Health Locus of Control scales, and the Hamilton Depression Rating Scale. The majority of patients diagnosed with advanced disease were admitted to hospital in the late/advanced stages of the disease. Multi-variant analysis showed that the most statistically significant positive predictor for early admittance in hospital is living with family and marital status while religiosity has a negative predictive value. The results indicate that 59.7% of respondents do not have depression, while the remainder do have some degree of depression. There was no statistically significant difference in the degree of depression between women who were diagnosed and treated early and those who were not. The employment status of the respondents was the only significant factor related to degree of depression. Although health locus of control and depression are not statistically significant predictors of early hospital treatment, the recommendation is that further studies focus on the implementation of MHLC and HDRS scales within the community. This could be useful in planning appropriate and

  4. Occupant Time Period of Thermal Adaption to Change of Outdoor Air Temperature in Naturally Ventilated Buildings

    DEFF Research Database (Denmark)

    liu, weiwei; Wargocki, Pawel; Xiong, Jing

    2014-01-01

    The present work proposed a method to determine time period of thermal adaption of occupants in naturally ventilated building, based on the relationship between their neutral temperatures and running mean outdoor air temperature. Based on the data of the field investigation, the subjects’ time...

  5. Investigation of unstable periodic space-time states in distributed active system with supercritical current

    International Nuclear Information System (INIS)

    Koronovskij, A.A.; Rempen, I.S.; Khramov, A.E.

    2003-01-01

    The set of the unstable periodic space-time states, characterizing the chaotic space-time dynamics of the electron beam with the supercritical current in the Pierce diode is discussed. The Lyapunov indicators of the revealed instable space-time states of the chaotic dynamics of the distributed self-excited system are calculated. It is shown that change in the set of the unstable periodic states in dependence on the Pierce parameter is determined by change in the various orbits stability, which is demonstrated by the values of senior Lyapunov unstable state index [ru

  6. Sensitivity of Hurst parameter estimation to periodic signals in time series and filtering approaches

    Science.gov (United States)

    Marković, D.; Koch, M.

    2005-09-01

    The influence of the periodic signals in time series on the Hurst parameter estimate is investigated with temporal, spectral and time-scale methods. The Hurst parameter estimates of the simulated periodic time series with a white noise background show a high sensitivity on the signal to noise ratio and for some methods, also on the data length used. The analysis is then carried on to the investigation of extreme monthly river flows of the Elbe River (Dresden) and of the Rhine River (Kaub). Effects of removing the periodic components employing different filtering approaches are discussed and it is shown that such procedures are a prerequisite for an unbiased estimation of H. In summary, our results imply that the first step in a time series long-correlation study should be the separation of the deterministic components from the stochastic ones. Otherwise wrong conclusions concerning possible memory effects may be drawn.

  7. Life time calculations for LCF loading combined with tensional hold periods

    International Nuclear Information System (INIS)

    Bocek, M.; Armas, A.; Piel, D.

    1983-01-01

    The life time in high amplitude strain cycling with tensional hold periods is analysed presuming that creep failure damage is life determining. The life fraction rule (LFR) is used to calculate the life time consumpted during the dwell period in strain controlled tests as well as during tensional hold time stress cycles. It follows from the present investigation that stress relaxation occurring during the strain hold periods plays the dominant influence upon the relationship between life and dwell time. For strong stress relaxation (e.g. high temperature) less damage is accumulated as compared to suppressed relaxation (low temperature). The damage in stress relaxation is calculated by means of the LFR and the results are compared to experiments conducted on Zircaloy-4 and the austenitic stainless stell Type AISI 304. From the very good agreement between both it is concluded that under the loading conditions considered, creep failure damage is the main life determining damage contribution. (orig.)

  8. Depression in the US population during the time periods surrounding the great recession.

    Science.gov (United States)

    Mehta, Kaushal; Kramer, Holly; Durazo-Arvizu, Ramon; Cao, Guichan; Tong, Liping; Rao, Murali

    2015-04-01

    To determine whether the time periods surrounding the 2008 US economic downturn were accompanied by an increase in prevalence of depression in the US adult population. We used data from the 24,182 adults aged ≥ 18 years who participated in the National Health and Nutrition Examination Survey during 2005-2012. A cross-sectional analysis was performed at each time period to determine prevalence of major and other depression as assessed by standardized questionnaires based on 9 criteria for major depressive episodes defined by DSM-IV. The demographic characteristics of the US population were similar across time periods except for the percentage of adults living in poverty, which increased from 26.43% during 2005-2006 to 33.46% during 2011-2012. The prevalence of major depression increased from 2.33% (95% CI, 1.64%-3.01%) during 2005-2006 to 3.49% (95% CI, 2.84%-4.03%) in 2009-2010 to 3.79% (95% CI, 3.01%-4.57%) in 2011-2012. Prevalence of other depression increased from 4.10% (95% CI, 3.37%-4.88%) in 2005-2006 to 4.79% (95% CI, 4.10%-5.44%) in the 2009-2010 period but then declined to 3.68% (95% CI, 2.84%-4.48%) in the 2011-2012 time period (P = .4). After adjustment for the distribution of age, sex, race/ethnicity, education, insurance status, and poverty status in the US adult noninstitutionalized population, each 2-year period after the 2005-2006 time period was associated with a 0.4% increase in major depression prevalence (P depression prevalence were noted by time period (P = .6). The time periods surrounding the recent economic recession were accompanied by a significant and sustained increase in major depression prevalence in the US population. It is plausible that the recession, given its strong, persistent, and negative effects on employment, job and housing security, and stock investments, contributed to the sustained increase in prevalence of major depression in the US population, but other factors associated with the recession time period could have

  9. Almost Periodic Solution for Memristive Neural Networks with Time-Varying Delays

    Directory of Open Access Journals (Sweden)

    Huaiqin Wu

    2013-01-01

    Full Text Available This paper is concerned with the dynamical stability analysis for almost periodic solution of memristive neural networks with time-varying delays. Under the framework of Filippov solutions, by applying the inequality analysis techniques, the existence and asymptotically almost periodic behavior of solutions are discussed. Based on the differential inclusions theory and Lyapunov functional approach, the stability issues of almost periodic solution are investigated, and a sufficient condition for the existence, uniqueness, and global exponential stability of the almost periodic solution is established. Moreover, as a special case, the condition which ensures the global exponential stability of a unique periodic solution is also presented for the considered memristive neural networks. Two examples are given to illustrate the validity of the theoretical results.

  10. The Sensitivity of Income Polarization - Time, length of accounting periods, equivalence scales, and income definitions

    DEFF Research Database (Denmark)

    Azhar, Hussain

    This study looks at polarization and its components’ sensitivity to assumptions about equivalence scales, income definition, ethical income distribution parameters, and the income accounting period. A representative sample of Danish individual incomes from 1984 to 2002 is utilised. Results show...... that polarization has increased over time, regardless of the applied measure, when the last part of the period is compared to the first part of the period. Primary causes being increased inequality (alienation) and faster income growth among high incomes relative to those in the middle of the distribution....... Increasing the accounting period confirms the reduction in inequality found for shorter periods, but polarization is virtually unchanged, because income group identification increases. Applying different equivalence scales does not change polarization ranking for different years, but identification ranks...

  11. Finding hidden periodic signals in time series - an application to stock prices

    Science.gov (United States)

    O'Shea, Michael

    2014-03-01

    Data in the form of time series appear in many areas of science. In cases where the periodicity is apparent and the only other contribution to the time series is stochastic in origin, the data can be `folded' to improve signal to noise and this has been done for light curves of variable stars with the folding resulting in a cleaner light curve signal. Stock index prices versus time are classic examples of time series. Repeating patterns have been claimed by many workers and include unusually large returns on small-cap stocks during the month of January, and small returns on the Dow Jones Industrial average (DJIA) in the months June through September compared to the rest of the year. Such observations imply that these prices have a periodic component. We investigate this for the DJIA. If such a component exists it is hidden in a large non-periodic variation and a large stochastic variation. We show how to extract this periodic component and for the first time reveal its yearly (averaged) shape. This periodic component leads directly to the `Sell in May and buy at Halloween' adage. We also drill down and show that this yearly variation emerges from approximately half of the underlying stocks making up the DJIA index.

  12. Boundedness and almost Periodicity in Time of Solutions of Evolutionary Variational Inequalities

    Science.gov (United States)

    Pankov, A. A.

    1983-04-01

    In this paper existence theorems are obtained for the solutions of abstract parabolic variational inequalities, which are bounded with respect to time (in the Stepanov and L^\\infty norms). The regularity and almost periodicity properties of such solutions are studied. Theorems are also established concerning their solvability in spaces of Besicovitch almost periodic functions. The majority of the results are obtained without any compactness assumptions. Bibliography: 30 titles.

  13. The Influence of Ambient Scent and Music on Patients' Anxiety in a Waiting Room of a Plastic Surgeon

    NARCIS (Netherlands)

    Fenko, Anna; Loock, Caroline

    2014-01-01

    OBJECTIVE: This study investigates the influence of ambient scent and music, and their combination, on patients' anxiety in a waiting room of a plastic surgeon. BACKGROUND: Waiting for an appointment with a plastic surgeon can increase a patient's anxiety. It is important to make the waiting time

  14. Practitioners' Perceptions of the Soccer Extra-Time Period: Implications for Future Research

    OpenAIRE

    Harper, Liam D.; Fothergill, Melissa; West, Daniel J.; Stevenson, Emma; Russell, Mark

    2016-01-01

    Qualitative research investigating soccer practitioners’ perceptions can allow researchers to create practical research investigations. The extra-time period of soccer is understudied compared to other areas of soccer research. Using an open-ended online survey containing eleven main and nine sub questions, we gathered the perceptions of extra-time from 46 soccer practitioners, all working for different professional soccer clubs. Questions related to current practices, views on extra-time reg...

  15. Regional differences in waiting time to pregnancy

    DEFF Research Database (Denmark)

    Juul, Svend; Karmaus, W; Olsen, Jørn

    1999-01-01

    of the pregnancies were planned (64%) and approximately 14% were the result of contraceptive failures. The study shows that smoking, body mass index, age and parity did not explain the differences in fecundity found between the centres. Regional differences in fecundity exist and the causes may be genetic or due...

  16. Improving generalized inverted index lock wait times

    Science.gov (United States)

    Borodin, A.; Mirvoda, S.; Porshnev, S.; Ponomareva, O.

    2018-01-01

    Concurrent operations on tree like data structures is a cornerstone of any database system. Concurrent operations intended for improving read\\write performance and usually implemented via some way of locking. Deadlock-free methods of concurrency control are known as tree locking protocols. These protocols provide basic operations(verbs) and algorithm (ways of operation invocations) for applying it to any tree-like data structure. These algorithms operate on data, managed by storage engine which are very different among RDBMS implementations. In this paper, we discuss tree locking protocol implementation for General inverted index (Gin) applied to multiversion concurrency control (MVCC) storage engine inside PostgreSQL RDBMS. After that we introduce improvements to locking protocol and provide usage statistics about evaluation of our improvement in very high load environment in one of the world’s largest IT company.

  17. Rank One Strange Attractors in Periodically Kicked Predator-Prey System with Time-Delay

    Science.gov (United States)

    Yang, Wenjie; Lin, Yiping; Dai, Yunxian; Zhao, Huitao

    2016-06-01

    This paper is devoted to the study of the problem of rank one strange attractor in a periodically kicked predator-prey system with time-delay. Our discussion is based on the theory of rank one maps formulated by Wang and Young. Firstly, we develop the rank one chaotic theory to delayed systems. It is shown that strange attractors occur when the delayed system undergoes a Hopf bifurcation and encounters an external periodic force. Then we use the theory to the periodically kicked predator-prey system with delay, deriving the conditions for Hopf bifurcation and rank one chaos along with the results of numerical simulations.

  18. Detecting method for crude oil price fluctuation mechanism under different periodic time series

    International Nuclear Information System (INIS)

    Gao, Xiangyun; Fang, Wei; An, Feng; Wang, Yue

    2017-01-01

    Highlights: • We proposed the concept of autoregressive modes to indicate the fluctuation patterns. • We constructed transmission networks for studying the fluctuation mechanism. • There are different fluctuation mechanism under different periodic time series. • Only a few types of autoregressive modes control the fluctuations in crude oil price. • There are cluster effects during the fluctuation mechanism of autoregressive modes. - Abstract: Current existing literatures can characterize the long-term fluctuation of crude oil price time series, however, it is difficult to detect the fluctuation mechanism specifically under short term. Because each fluctuation pattern for one short period contained in a long-term crude oil price time series have dynamic characteristics of diversity; in other words, there exhibit various fluctuation patterns in different short periods and transmit to each other, which reflects the reputedly complicate and chaotic oil market. Thus, we proposed an incorporated method to detect the fluctuation mechanism, which is the evolution of the different fluctuation patterns over time from the complex network perspective. We divided crude oil price time series into segments using sliding time windows, and defined autoregressive modes based on regression models to indicate the fluctuation patterns of each segment. Hence, the transmissions between different types of autoregressive modes over time form a transmission network that contains rich dynamic information. We then capture transmission characteristics of autoregressive modes under different periodic time series through the structure features of the transmission networks. The results indicate that there are various autoregressive modes with significantly different statistical characteristics under different periodic time series. However, only a few types of autoregressive modes and transmission patterns play a major role in the fluctuation mechanism of the crude oil price, and these

  19. Exact dynamics of a one dimensional Bose gas in a periodic time-dependent harmonic trap

    Science.gov (United States)

    Scopa, Stefano; Unterberger, Jéremie; Karevski, Dragi

    2018-05-01

    We study the unitary dynamics of a 1D gas of hard-core bosons trapped into a harmonic potential which varies periodically in time with frequency . Such periodic systems can be classified into orbits of different monodromies corresponding to two different physical situations, namely the case in which the bosonic cloud remains stable during the time-evolution and the case where it turns out to be unstable. In the present work we derive in the large particle number limit exact results for the stroboscopic evolution of the energy and particle densities in both physical situations.

  20. A Time-Delayed Mathematical Model for Tumor Growth with the Effect of a Periodic Therapy.

    Science.gov (United States)

    Xu, Shihe; Wei, Xiangqing; Zhang, Fangwei

    2016-01-01

    A time-delayed mathematical model for tumor growth with the effect of periodic therapy is studied. The establishment of the model is based on the reaction-diffusion dynamics and mass conservation law and is considered with a time delay in cell proliferation process. Sufficient conditions for the global stability of tumor free equilibrium are given. We also prove that if external concentration of nutrients is large the tumor will not disappear and the conditions under which there exist periodic solutions to the model are also determined. Results are illustrated by computer simulations.

  1. A Time-Delayed Mathematical Model for Tumor Growth with the Effect of a Periodic Therapy

    Directory of Open Access Journals (Sweden)

    Shihe Xu

    2016-01-01

    Full Text Available A time-delayed mathematical model for tumor growth with the effect of periodic therapy is studied. The establishment of the model is based on the reaction-diffusion dynamics and mass conservation law and is considered with a time delay in cell proliferation process. Sufficient conditions for the global stability of tumor free equilibrium are given. We also prove that if external concentration of nutrients is large the tumor will not disappear and the conditions under which there exist periodic solutions to the model are also determined. Results are illustrated by computer simulations.

  2. Periodic review inventory policy for non-instantaneous deteriorating items with time dependent deterioration rate

    Directory of Open Access Journals (Sweden)

    Anwesha Samanta

    2015-09-01

    Full Text Available The paper studies a periodic review inventory model with no shortages and different demand rates during pre- and post- deterioration periods . Deterioration of units start after a fixed time interval, and the deterioration rate is time dependent. The model determines the optimal reorder interval and the optimal order quantity so as to minimize the total cost per unit length of an inventory cycle. An extension of the model to include price discount has been further considered. Numerical examples are presented to illustrate the model and a sensitivity analysis is also reported.

  3. Poster - 26: Electronic Waiting Room Management for a busy Cancer Centre

    Energy Technology Data Exchange (ETDEWEB)

    Kildea, John; Hijal, Tarek [McGill University Health Center (Canada)

    2016-08-15

    We describe an electronic waiting room management system that we have developed and deployed in our cancer centre. Our system connects with our electronic medical records systems, gathers data for a machine learning algorithm to predict future patient waiting times, and is integrated with a mobile phone app. The system has been in operation for over nine months and has led to reduced lines, calmer waiting rooms and overwhelming patient and staff satisfaction.

  4. Poster - 26: Electronic Waiting Room Management for a busy Cancer Centre

    International Nuclear Information System (INIS)

    Kildea, John; Hijal, Tarek

    2016-01-01

    We describe an electronic waiting room management system that we have developed and deployed in our cancer centre. Our system connects with our electronic medical records systems, gathers data for a machine learning algorithm to predict future patient waiting times, and is integrated with a mobile phone app. The system has been in operation for over nine months and has led to reduced lines, calmer waiting rooms and overwhelming patient and staff satisfaction.

  5. WAITING FOR GODOT - ABSURD TEATER

    OpenAIRE

    Thorup, Rasmus; Leitthof, Anneliese; Kock, Felizia; Johansson, Lars; Moustgaard, Mie; Rosenkrands, Tobias; Staalhøj, Sarah; Jeppesen, Freja

    2013-01-01

    This project aims to reassess and discuss the different interpretations of Samuel Beckett’s play Waiting for Godot, made by Martin Esslin and Michael Y. Bennett. The analytical tools needed to enable the reassessment is found in the dimensional courses of Philosophy and Scientific theory (Da: Filosofi og Videnskabsteori) and Text-analysis (Da: Tekst og Tegn) and the discussion is based on Esslin’s The Theatre of The Absurd and Bennett’s Reassessing The Theatre of The Absurd. The conclusion is...

  6. Waiting in the queue on Hotelling’s Main Street

    NARCIS (Netherlands)

    Peters, H.J.M.; Schröder, M.J.W.; Vermeulen, A.J.

    2015-01-01

    We consider a variant of Hotelling’s location model that was proposed by Kohlberg (1983): when choosing a firm, consumers take travel time and also (expected) waiting time, which again depends on the number of consumers choosing that firm, into consideration. If we assume that firms are symmetric,

  7. A national analysis of dental waiting lists and point-in-time geographic access to subsidised dental care: can geographic access be improved by offering public dental care through private dental clinics?

    Science.gov (United States)

    Dudko, Yevgeni; Kruger, Estie; Tennant, Marc

    2017-01-01

    Australia is one of the least densely populated countries in the world, with a population concentrated on or around coastal areas. Up to 33% of the Australian population are likely to have untreated dental decay, while people with inadequate dentition (fewer than 21 teeth) account for up to 34% of Australian adults. Historically, inadequate access to public dental care has resulted in long waiting lists, received much media coverage and been the subject of a new federal and state initiative. The objective of this research was to gauge the potential for reducing the national dental waiting list through geographical advantage, which could arise from subcontracting the delivery of subsidised dental care to the existing network of private dental clinics across Australia. Eligible population data were collected from the Australian Bureau of Statistics website. Waiting list data from across Australia were collected from publicly available sources and confirmed through direct communication with each individual state or territory dental health body. Quantum geographic information system software was used to map distribution of the eligible population across Australia by statistical area, and to plot locations of government and private dental clinics. Catchment areas of 5 km for metropolitan clinics and 5 km and 50 km for rural clinics were defined. The number of people on the waiting list and those eligible for subsidised dental care covered by each of the catchment areas was calculated. Percentage of the eligible population and those on the waiting list that could benefit from the potential improvement in geographic access was ascertained for metropolitan and rural residents. Fifty three percent of people on the waiting list resided within metropolitan areas. Rural and remote residents made up 47% of the population waiting to receive care. The utilisation of both government and private dental clinics for the delivery of subsidised dental care to the eligible population

  8. The Improved Adaptive Silence Period Algorithm over Time-Variant Channels in the Cognitive Radio System

    Directory of Open Access Journals (Sweden)

    Jingbo Zhang

    2018-01-01

    Full Text Available In the field of cognitive radio spectrum sensing, the adaptive silence period management mechanism (ASPM has improved the problem of the low time-resource utilization rate of the traditional silence period management mechanism (TSPM. However, in the case of the low signal-to-noise ratio (SNR, the ASPM algorithm will increase the probability of missed detection for the primary user (PU. Focusing on this problem, this paper proposes an improved adaptive silence period management (IA-SPM algorithm which can adaptively adjust the sensing parameters of the current period in combination with the feedback information from the data communication with the sensing results of the previous period. The feedback information in the channel is achieved with frequency resources rather than time resources in order to adapt to the parameter change in the time-varying channel. The Monte Carlo simulation results show that the detection probability of the IA-SPM is 10–15% higher than that of the ASPM under low SNR conditions.

  9. Monostable traveling waves for a time-periodic and delayed nonlocal reaction-diffusion equation

    Science.gov (United States)

    Li, Panxiao; Wu, Shi-Liang

    2018-04-01

    This paper is concerned with a time-periodic and delayed nonlocal reaction-diffusion population model with monostable nonlinearity. Under quasi-monotone or non-quasi-monotone assumptions, it is known that there exists a critical wave speed c_*>0 such that a periodic traveling wave exists if and only if the wave speed is above c_*. In this paper, we first prove the uniqueness of non-critical periodic traveling waves regardless of whether the model is quasi-monotone or not. Further, in the quasi-monotone case, we establish the exponential stability of non-critical periodic traveling fronts. Finally, we illustrate the main results by discussing two types of death and birth functions arising from population biology.

  10. Optimising radiation outcomes, scheduling patient waiting lists for maximum population tumour control

    International Nuclear Information System (INIS)

    Ebert, M.A.; Jennings, L.; Kearvell, R.; Bydder, S.

    2011-01-01

    Full text: Delays in the commencement of radiotherapy, possibly due to resource constraints, are known to impact on control-related outcomes. We sought an objective solution for patient prioritisation based on tumour control probability (TCP). With a utilitarian objective for maximising TCP in a population of M patients, with patient i waiting a time between diagnosis and treatment of Ti and a mean wait time of TMean, the optimisation problem is as shown. A linear-quadratic/Poissonian model for cell survival/TCP was considered including cell doubling during the wait time. Solutions to several distributions of patient population characteristics were examined together with the expected change in TCP for the population and individuals. An analytical solution to the optimisation problem was found which gives the optimal wait time for each patient as a function of the distribution of radiobiological characteristics in the population. This solution does not allow a negativity constraint on an individual's optimised waiting time so a waiting list simulation was developed to enforce that. Optimal wait time distributions were calculated for situations where patients are allocated distinct diagnostic groups (sharing radiobiological parameters) and for a (log-normal) distribution of doubling times in the population. In order to meet the utilitarian objective, the optimal solutions require patients with rapid cell doubling times to be accelerated up the waiting list at the expense of those with slowly proliferating tumours. The net population benefit however is comparable to or greater then the expected benefit from beam intensity modulation or dose escalation.

  11. Minimizing makespan for a no-wait flowshop using genetic algorithm

    Indian Academy of Sciences (India)

    This paper explains minimization of makespan or total completion time .... lead to a natural reduction of the no-wait flow shop problem to the travelling sales- ... FCH can also be applied in real time scheduling and rescheduling for no-wait flow.

  12. A Gaussian Process Based Online Change Detection Algorithm for Monitoring Periodic Time Series

    Energy Technology Data Exchange (ETDEWEB)

    Chandola, Varun [ORNL; Vatsavai, Raju [ORNL

    2011-01-01

    Online time series change detection is a critical component of many monitoring systems, such as space and air-borne remote sensing instruments, cardiac monitors, and network traffic profilers, which continuously analyze observations recorded by sensors. Data collected by such sensors typically has a periodic (seasonal) component. Most existing time series change detection methods are not directly applicable to handle such data, either because they are not designed to handle periodic time series or because they cannot operate in an online mode. We propose an online change detection algorithm which can handle periodic time series. The algorithm uses a Gaussian process based non-parametric time series prediction model and monitors the difference between the predictions and actual observations within a statistically principled control chart framework to identify changes. A key challenge in using Gaussian process in an online mode is the need to solve a large system of equations involving the associated covariance matrix which grows with every time step. The proposed algorithm exploits the special structure of the covariance matrix and can analyze a time series of length T in O(T^2) time while maintaining a O(T) memory footprint, compared to O(T^4) time and O(T^2) memory requirement of standard matrix manipulation methods. We experimentally demonstrate the superiority of the proposed algorithm over several existing time series change detection algorithms on a set of synthetic and real time series. Finally, we illustrate the effectiveness of the proposed algorithm for identifying land use land cover changes using Normalized Difference Vegetation Index (NDVI) data collected for an agricultural region in Iowa state, USA. Our algorithm is able to detect different types of changes in a NDVI validation data set (with ~80% accuracy) which occur due to crop type changes as well as disruptive changes (e.g., natural disasters).

  13. Practitioners' Perceptions of the Soccer Extra-Time Period: Implications for Future Research.

    Directory of Open Access Journals (Sweden)

    Liam D Harper

    Full Text Available Qualitative research investigating soccer practitioners' perceptions can allow researchers to create practical research investigations. The extra-time period of soccer is understudied compared to other areas of soccer research. Using an open-ended online survey containing eleven main and nine sub questions, we gathered the perceptions of extra-time from 46 soccer practitioners, all working for different professional soccer clubs. Questions related to current practices, views on extra-time regulations, and ideas for future research. Using inductive content analysis, the following general dimensions were identified: 'importance of extra-time', 'rule changes', 'efficacy of extra-time hydro-nutritional provision', 'nutritional timing', 'future research directions', 'preparatory modulations' and 'recovery'. The majority of practitioners (63% either agreed or strongly agreed that extra-time is an important period for determining success in knockout football match-play. When asked if a fourth substitution should be permitted in extra-time, 67% agreed. The use of hydro-nutritional strategies prior to extra-time was predominately considered important or very important. However; only 41% of practitioners felt that it was the most important time point for the use of nutritional products. A similar number of practitioners account (50% and do not (50% account for the potential of extra-time when training and preparing players and 89% of practitioners stated that extra-time influences recovery practices following matches. In the five minute break prior to extra-time, the following practices (in order of priority were advocated to players: hydration, energy provision, massage, and tactical preparations. Additionally, 87% of practitioners advocate a particular nutritional supplementation strategy prior to extra-time. In order of importance, practitioners see the following as future research areas: nutritional interventions, fatigue responses, acute injury risk

  14. Practitioners' Perceptions of the Soccer Extra-Time Period: Implications for Future Research.

    Science.gov (United States)

    Harper, Liam D; Fothergill, Melissa; West, Daniel J; Stevenson, Emma; Russell, Mark

    2016-01-01

    Qualitative research investigating soccer practitioners' perceptions can allow researchers to create practical research investigations. The extra-time period of soccer is understudied compared to other areas of soccer research. Using an open-ended online survey containing eleven main and nine sub questions, we gathered the perceptions of extra-time from 46 soccer practitioners, all working for different professional soccer clubs. Questions related to current practices, views on extra-time regulations, and ideas for future research. Using inductive content analysis, the following general dimensions were identified: 'importance of extra-time', 'rule changes', 'efficacy of extra-time hydro-nutritional provision', 'nutritional timing', 'future research directions', 'preparatory modulations' and 'recovery'. The majority of practitioners (63%) either agreed or strongly agreed that extra-time is an important period for determining success in knockout football match-play. When asked if a fourth substitution should be permitted in extra-time, 67% agreed. The use of hydro-nutritional strategies prior to extra-time was predominately considered important or very important. However; only 41% of practitioners felt that it was the most important time point for the use of nutritional products. A similar number of practitioners account (50%) and do not (50%) account for the potential of extra-time when training and preparing players and 89% of practitioners stated that extra-time influences recovery practices following matches. In the five minute break prior to extra-time, the following practices (in order of priority) were advocated to players: hydration, energy provision, massage, and tactical preparations. Additionally, 87% of practitioners advocate a particular nutritional supplementation strategy prior to extra-time. In order of importance, practitioners see the following as future research areas: nutritional interventions, fatigue responses, acute injury risk, recovery

  15. On time-periodic Navier-Stokes flows with fast spatial decay in the whole space

    Czech Academy of Sciences Publication Activity Database

    Nakatsuka, Tomoyuki

    2018-01-01

    Roč. 4, č. 1 (2018), s. 51-67 ISSN 2296-9020 Institutional support: RVO:67985840 Keywords : Navier-Stokes equation * time-periodic solution * asymptotic property Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics https://link.springer.com/article/10. 1007 %2Fs41808-018-0011-8

  16. Four positive periodic solutions of a discrete time Lotka-Volterra competitive system with harvesting terms

    Directory of Open Access Journals (Sweden)

    Xinggui Liu

    2011-01-01

    Full Text Available In this paper, by using Mawhin's continuation theorem of coincidence degree theory, we establish the existence of at least four positive periodic solutions for a discrete time Lotka-Volterra competitive system with harvesting terms. An example is given to illustrate the effectiveness of our results.

  17. On time-periodic Navier-Stokes flows with fast spatial decay in the whole space

    Czech Academy of Sciences Publication Activity Database

    Nakatsuka, Tomoyuki

    2018-01-01

    Roč. 4, č. 1 (2018), s. 51-67 ISSN 2296-9020 Institutional support: RVO:67985840 Keywords : Navier-Stokes equation * time-periodic solution * asymptotic property Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics https://link.springer.com/article/10.1007%2Fs41808-018-0011-8

  18. Reliability of fitness tests using methods and time periods common in sport and occupational management.

    Science.gov (United States)

    Burnstein, Bryan D; Steele, Russell J; Shrier, Ian

    2011-01-01

    Fitness testing is used frequently in many areas of physical activity, but the reliability of these measurements under real-world, practical conditions is unknown. To evaluate the reliability of specific fitness tests using the methods and time periods used in the context of real-world sport and occupational management. Cohort study. Eighteen different Cirque du Soleil shows. Cirque du Soleil physical performers who completed 4 consecutive tests (6-month intervals) and were free of injury or illness at each session (n = 238 of 701 physical performers). Performers completed 6 fitness tests on each assessment date: dynamic balance, Harvard step test, handgrip, vertical jump, pull-ups, and 60-second jump test. We calculated the intraclass coefficient (ICC) and limits of agreement between baseline and each time point and the ICC over all 4 time points combined. Reliability was acceptable (ICC > 0.6) over an 18-month time period for all pairwise comparisons and all time points together for the handgrip, vertical jump, and pull-up assessments. The Harvard step test and 60-second jump test had poor reliability (ICC < 0.6) between baseline and other time points. When we excluded the baseline data and calculated the ICC for 6-month, 12-month, and 18-month time points, both the Harvard step test and 60-second jump test demonstrated acceptable reliability. Dynamic balance was unreliable in all contexts. Limit-of-agreement analysis demonstrated considerable intraindividual variability for some tests and a learning effect by administrators on others. Five of the 6 tests in this battery had acceptable reliability over an 18-month time frame, but the values for certain individuals may vary considerably from time to time for some tests. Specific tests may require a learning period for administrators.

  19. Waiting is the hardest part: anticipating medical test results affects processing and recall of important information.

    Science.gov (United States)

    Portnoy, David B

    2010-07-01

    Waiting for medical test results that signal physical harm can be a stressful and potentially psychologically harmful experience. Despite this, interventionists and physicians often use this wait time to deliver behavior change messages and other important information about the test, possible results and its implications. This study examined how "bracing" for a medical test result impacts cognitive processing, as well as recall of information delivered during this period. Healthy U.S. university students (N = 150) were tested for a deficiency of a fictitious saliva biomarker that was said to be predictive of long-term health problems using a 2 (Test Result) x 2 (Expected immediacy of result: 10 min, 1 month) factorial design. Participants expecting to get the test result shortly should have been bracing for the result. While waiting for the test results participants completed measures of cognitive processing. After participants received the test result, recall of information about the biomarker was tested in addition to cognitive measures. One week later, participants who were originally told they did not have the deficiency had their recall assessed again. Results showed that anticipating an imminent test result increased cognitive distraction in the processing of information and lowered recall of information about the test and the biomarker. These results suggest that delivering critical information to patients after administering a test and immediately before giving the results may not be optimal.

  20. Efficient Fourier-based algorithms for time-periodic unsteady problems

    Science.gov (United States)

    Gopinath, Arathi Kamath

    2007-12-01

    This dissertation work proposes two algorithms for the simulation of time-periodic unsteady problems via the solution of Unsteady Reynolds-Averaged Navier-Stokes (URANS) equations. These algorithms use a Fourier representation in time and hence solve for the periodic state directly without resolving transients (which consume most of the resources in a time-accurate scheme). In contrast to conventional Fourier-based techniques which solve the governing equations in frequency space, the new algorithms perform all the calculations in the time domain, and hence require minimal modifications to an existing solver. The complete space-time solution is obtained by iterating in a fifth pseudo-time dimension. Various time-periodic problems such as helicopter rotors, wind turbines, turbomachinery and flapping-wings can be simulated using the Time Spectral method. The algorithm is first validated using pitching airfoil/wing test cases. The method is further extended to turbomachinery problems, and computational results verified by comparison with a time-accurate calculation. The technique can be very memory intensive for large problems, since the solution is computed (and hence stored) simultaneously at all time levels. Often, the blade counts of a turbomachine are rescaled such that a periodic fraction of the annulus can be solved. This approximation enables the solution to be obtained at a fraction of the cost of a full-scale time-accurate solution. For a viscous computation over a three-dimensional single-stage rescaled compressor, an order of magnitude savings is achieved. The second algorithm, the reduced-order Harmonic Balance method is applicable only to turbomachinery flows, and offers even larger computational savings than the Time Spectral method. It simulates the true geometry of the turbomachine using only one blade passage per blade row as the computational domain. In each blade row of the turbomachine, only the dominant frequencies are resolved, namely

  1. Development of an Information Model for Kidney Transplant Wait List.

    Science.gov (United States)

    Bircan, Hüseyin Yüce; Özçelik, Ümit; Uysal, Nida; Demirağ, Alp; Haberal, Mehmet

    2015-11-01

    Deceased-donor kidney transplant is unique among surgical procedures that are an urgent procedure performed in an elective population. It has not been possible to accurately determine when a given patient will be called for transplant. Patients on the active transplant list can be called for a transplant at any time. As a result, every effort must be made to optimize their health according to best practices and published clinical practice guidelines. Once the patient is placed on the transplant wait list after undergoing an initial extensive evaluation, continued surveillance is required. Therefore, we developed a kidney transplant wait list surveillance software program that alerts organ transplant coordinator on time regarding which patients need a work-up. The new designed software has a database of our waiting patients with their completed and pending controls. The software also has built-in functions to warn the responsible staff with an E-mail. If one of the controls of a recipient delayed, the software sends an automated E-mail to the staff regarding the patients delayed controls. The software is a Web application that works on any platform with a Web browser and Internet connection and allows access by multiple users. The software has been developed with NET platform. The database is SQL server. The software has the following functions: patient communication info, search, alert list, alert E-mail, control entry, and system management. As of January 2014, a total of 21 000 patients were registered on the National Kidney Transplant wait list in Turkey and the kidney transplant wait list had been expanding by 2000 to 3000 patients each year. Therefore computerized wait list programs are crucial to help to transplant centers to keep their patients up-to-date on time.

  2. Effects of combined linear and nonlinear periodic training on physical fitness and competition times in finswimmers.

    Science.gov (United States)

    Yu, Kyung-Hun; Suk, Min-Hwa; Kang, Shin-Woo; Shin, Yun-A

    2014-10-01

    The purpose of this study was to investigate the effect of combined linear and nonlinear periodic training on physical fitness and competition times in finswimmers. The linear resistance training model (6 days/week) and nonlinear underwater training (4 days/week) were applied to 12 finswimmers (age, 16.08± 1.44 yr; career, 3.78± 1.90 yr) for 12 weeks. Body composition measures included weight, body mass index (BMI), percent fat, and fat-free mass. Physical fitness measures included trunk flexion forward, trunk extension backward, sargent jump, 1-repetition-maximum (1 RM) squat, 1 RM dead lift, knee extension, knee flexion, trunk extension, trunk flexion, and competition times. Body composition and physical fitness were improved after the 12-week periodic training program. Weight, BMI, and percent fat were significantly decreased, and trunk flexion forward, trunk extension backward, sargent jump, 1 RM squat, 1 RM dead lift, and knee extension (right) were significantly increased. The 50- and 100-m times significantly decreased in all 12 athletes. After 12 weeks of training, all finswimmers who participated in this study improved their times in a public competition. These data indicate that combined linear and nonlinear periodic training enhanced the physical fitness and competition times in finswimmers.

  3. Time to reach a given level of number of neutrons is stochastic analog of reactor period

    International Nuclear Information System (INIS)

    Ryazanov, V.V.

    2012-01-01

    In theory and in practice the operation of nuclear reactors to control the safety of the reactor is widely used deterministic value - the period of the reactor. It is proposed along with the period of the reactor using a stochastic analogue of this magnitude - a random amount of time to achieve a given level of a random process for the number of neutrons in the reactor. The paper discusses various features of the behavior of the mean and variance of time to achieve a specified level. This kind of features can be associated with impaired behavior of the reactor system. Introduced the value of time required to reach the level can be used to monitor and improve the safety of nuclear power plants

  4. Periodic Solution of Second-Order Hamiltonian Systems with a Change Sign Potential on Time Scales

    Directory of Open Access Journals (Sweden)

    You-Hui Su

    2009-01-01

    Full Text Available This paper is concerned with the second-order Hamiltonian system on time scales 𝕋 of the form uΔΔ(ρ(t+μb(t|u(t|μ−2u(t+∇¯H(t,u(t=0, Δ-a.e. t∈[0,T]𝕋 , u(0−u(T=uΔ(ρ(0−uΔ(ρ(T=0, where 0,T∈𝕋. By using the minimax methods in critical theory, an existence theorem of periodic solution for the above system is established. As an application, an example is given to illustrate the result. This is probably the first time the existence of periodic solutions for second-order Hamiltonian system on time scales has been studied by critical theory.

  5. Passive magnetic bearing systems stabilizer/bearing utilizing time-averaging of a periodic magnetic field

    Science.gov (United States)

    Post, Richard F.

    2017-10-03

    A high-stiffness stabilizer/bearings for passive magnetic bearing systems is provide where the key to its operation resides in the fact that when the frequency of variation of the repelling forces of the periodic magnet array is large compared to the reciprocal of the growth time of the unstable motion, the rotating system will feel only the time-averaged value of the force. When the time-averaged value of the force is radially repelling by the choice of the geometry of the periodic magnet array, the Earnshaw-related unstable hit motion that would occur at zero rotational speed is suppressed when the system is rotating at operating speeds.

  6. Storing quantum information in XXZ spin rings with periodically time-controlled interactions

    International Nuclear Information System (INIS)

    Giampaolo, S M; Illuminati, F; Mazzarella, G

    2005-01-01

    We introduce a general scheme to realize massive quantum memories in simple systems of interacting qubits. Such systems are described by spin rings with XXZ intersite couplings of suitably time-periodically controlled amplitudes. We show that initially localized excitations undergo perfect periodic revivals, allowing for the simultaneous storage of arbitrary sets of different local states. This novel approach to the problem of storing quantum information hints at a new way to control and suppress the effect of decoherence on a quantum computer realized in a system with nonvanishing interactions between the constituent qubits

  7. Storing quantum information in XXZ spin rings with periodically time-controlled interactions

    Energy Technology Data Exchange (ETDEWEB)

    Giampaolo, S M; Illuminati, F; Mazzarella, G [Dipartimento di Fisica ' E. R. Caianiello' , Universita di Salerno, INFM UdR di Salerno, INFN Sezione di Napoli, Gruppo Collegato di Salerno, Via S. Allende, 84081 Baronissi, SA (Italy)

    2005-10-01

    We introduce a general scheme to realize massive quantum memories in simple systems of interacting qubits. Such systems are described by spin rings with XXZ intersite couplings of suitably time-periodically controlled amplitudes. We show that initially localized excitations undergo perfect periodic revivals, allowing for the simultaneous storage of arbitrary sets of different local states. This novel approach to the problem of storing quantum information hints at a new way to control and suppress the effect of decoherence on a quantum computer realized in a system with nonvanishing interactions between the constituent qubits.

  8. Plasticity of the intrinsic period of the human circadian timing system.

    Directory of Open Access Journals (Sweden)

    Frank A J L Scheer

    2007-08-01

    Full Text Available Human expeditions to Mars will require adaptation to the 24.65-h Martian solar day-night cycle (sol, which is outside the range of entrainment of the human circadian pacemaker under lighting intensities to which astronauts are typically exposed. Failure to entrain the circadian time-keeping system to the desired rest-activity cycle disturbs sleep and impairs cognitive function. Furthermore, differences between the intrinsic circadian period and Earth's 24-h light-dark cycle underlie human circadian rhythm sleep disorders, such as advanced sleep phase disorder and non-24-hour sleep-wake disorders. Therefore, first, we tested whether exposure to a model-based lighting regimen would entrain the human circadian pacemaker at a normal phase angle to the 24.65-h Martian sol and to the 23.5-h day length often required of astronauts during short duration space exploration. Second, we tested here whether such prior entrainment to non-24-h light-dark cycles would lead to subsequent modification of the intrinsic period of the human circadian timing system. Here we show that exposure to moderately bright light ( approximately 450 lux; approximately 1.2 W/m(2 for the second or first half of the scheduled wake episode is effective for entraining individuals to the 24.65-h Martian sol and a 23.5-h day length, respectively. Estimations of the circadian periods of plasma melatonin, plasma cortisol, and core body temperature rhythms collected under forced desynchrony protocols revealed that the intrinsic circadian period of the human circadian pacemaker was significantly longer following entrainment to the Martian sol as compared to following entrainment to the 23.5-h day. The latter finding of after-effects of entrainment reveals for the first time plasticity of the period of the human circadian timing system. Both findings have important implications for the treatment of circadian rhythm sleep disorders and human space exploration.

  9. Copper, nickel and lead in lichen and tree bark transplants over different periods of time

    Energy Technology Data Exchange (ETDEWEB)

    Baptista, Mafalda S. [CIIMAR, Rua dos Bragas, 289, 4050-123 Porto (Portugal)], E-mail: abaptista@fc.up.pt; Vasconcelos, M. Teresa S.D. [CIIMAR, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Chemistry Department, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 687, 4169-071 Porto (Portugal)], E-mail: mtvascon@fc.up.pt; Cabral, Joao Paulo [CIIMAR, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Botany Department, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 1191, 4150-181 Porto (Portugal)], E-mail: jpcabral@fc.up.pt; Freitas, M. Carmo [ITN - Technological and Nuclear Institute, Reactor E.N. 10, 2686-953 Sacavem (Portugal)], E-mail: cfreitas@itn.mcies.pt; Pacheco, Adriano M.G. [CVRM-IST - Technical University of Lisbon, Avenida Rovisco Pais, 1, 1049-001 Lisbon (Portugal)], E-mail: apacheco@ist.utl.pt

    2008-01-15

    This work aimed at comparing the dynamics of atmospheric metal accumulation by the lichen Flavoparmelia caperata and bark of Platanus hybrida over different periods of time. Transplants were exposed in three Portuguese coastal cities. Samples were retrieved (1) every 2 months (discontinuous exposure), or (2) after 2-, 4-, 6-, 8- and 10-month periods (continuous exposure), and analysed for Cu, Ni and Pb. Airborne accumulation of metals was essentially independent of climatic factors. For both biomonitors [Pb] > [Ni] > [Cu] but Pb was the only element for which a consistent pattern of accumulation was observed, with the bark outperforming the lichen. The longest exposure periods hardly ever corresponded to the highest accumulation. This might have been partly because the biomonitors bound and released metals throughout the exposure, each with its own dynamics of accumulation, but both according to the environmental metal availability. - Lichen and tree bark have distinct dynamics of airborne metal accumulation.

  10. Copper, nickel and lead in lichen and tree bark transplants over different periods of time

    International Nuclear Information System (INIS)

    Baptista, Mafalda S.; Vasconcelos, M. Teresa S.D.; Cabral, Joao Paulo; Freitas, M. Carmo; Pacheco, Adriano M.G.

    2008-01-01

    This work aimed at comparing the dynamics of atmospheric metal accumulation by the lichen Flavoparmelia caperata and bark of Platanus hybrida over different periods of time. Transplants were exposed in three Portuguese coastal cities. Samples were retrieved (1) every 2 months (discontinuous exposure), or (2) after 2-, 4-, 6-, 8- and 10-month periods (continuous exposure), and analysed for Cu, Ni and Pb. Airborne accumulation of metals was essentially independent of climatic factors. For both biomonitors [Pb] > [Ni] > [Cu] but Pb was the only element for which a consistent pattern of accumulation was observed, with the bark outperforming the lichen. The longest exposure periods hardly ever corresponded to the highest accumulation. This might have been partly because the biomonitors bound and released metals throughout the exposure, each with its own dynamics of accumulation, but both according to the environmental metal availability. - Lichen and tree bark have distinct dynamics of airborne metal accumulation

  11. Nonequilibrium steady states and resonant tunneling in time-periodically driven systems with interactions

    Science.gov (United States)

    Qin, Tao; Hofstetter, Walter

    2018-03-01

    Time-periodically driven systems are a versatile toolbox for realizing interesting effective Hamiltonians. Heating, caused by excitations to high-energy states, is a challenge for experiments. While most setups so far address the relatively weakly interacting regime, it is of general interest to study heating in strongly correlated systems. Using Floquet dynamical mean-field theory, we study nonequilibrium steady states (NESS) in the Falicov-Kimball model, with time-periodically driven kinetic energy or interaction. We systematically investigate the nonequilibrium properties of the NESS. For a driven kinetic energy, we show that resonant tunneling, where the interaction is an integer multiple of the driving frequency, plays an important role in the heating. In the strongly correlated regime, we show that this can be well understood using Fermi's golden rule and the Schrieffer-Wolff transformation for a time-periodically driven system. We furthermore demonstrate that resonant tunneling can be used to control the population of Floquet states to achieve "photodoping." For driven interactions introduced by an oscillating magnetic field near a widely adopted Feshbach resonance, we find that the double occupancy is strongly modulated. Our calculations apply to shaken ultracold-atom systems and to solid-state systems in a spatially uniform but time-dependent electric field. They are also closely related to lattice modulation spectroscopy. Our calculations are helpful to understand the latest experiments on strongly correlated Floquet systems.

  12. Abundant spontaneous VLFE activities in Cascadia during ETS and inter-ETS time periods

    Science.gov (United States)

    Ghosh, A.; Hutchison, A. A.; Hawthorne, J.

    2017-12-01

    Very low frequency earthquakes (VLFEs) are discrete seismic events associated with episodic tremor and slip (ETS) events. They are rich in 20-50s energy and depleted in higher frequencies compared to regular local earthquakes of similar magnitudes. VLFEs can be as large as Mw 4.0, and potentially release much more seismic moment than the tremor/LFE activities, making them a critical event determining stress evolution during slow earthquakes [Ghosh et al., 2015]. Their underlying physics and relationship with tremor/LFE, however, are still unclear. In Cascadia, the majority of the VLFEs found so far are clustered near the areas of high geodetic slip during ETS events [Ghosh et al., 2015; Hutchison and Ghosh, 2016]. Interestingly, we found VLFE activity has its own dynamics and can occur independent of tremor/LFE activity. For example, during the 2014 ETS event in northern Cascadia, VLFEs are found to be asynchronous with tremor activity, both in space and time [Hutchison and Ghosh, 2016]. We use a matched filter technique to detect thousands of VLFEs over an ETS-cycle, and perhaps more interestingly, even between ETS events. VLFE activities peak during ETS events, but significant VLFE activity is detected during the inter-ETS time period. Analyses of strainmeter data near the VLFE locations suggest statistically significant strain rate increases during VLFE time periods compared to the background. We suggest that VLFE is a distinct type of seismic radiation different from tremor/LFE, and can operate independently from tremor activities. This is in contrast to a model suggesting that VLFE signals may be a result of many LFE signals arriving at seismic stations in a short time period [Gomberg et al., 2016]. We are making a consistent catalog of VLFE in Cascadia for longer time period. Systematic study of VLFEs is going to provide new insights into the mechanism of slow earthquakes and its relationship with tremor/LFE and slow slip.

  13. Stability of horizontal viscous fluid layers in a vertical arbitrary time periodic electric field

    Science.gov (United States)

    Bandopadhyay, Aditya; Hardt, Steffen

    2017-12-01

    The stability of a horizontal interface between two viscous fluids, one of which is conducting and the other is dielectric, acted upon by a vertical time-periodic electric field is considered theoretically. The two fluids are bounded by electrodes separated by a finite distance. For an applied ac electric field, the unstable interface deforms in a time periodic manner, owing to the time dependent Maxwell stress, and is characterized by the oscillation frequency which may or may not be the same as the frequency of the ac electric field. The stability curve, which relates the critical voltage, manifested through the Mason number—the ratio of normal electric stress and viscous stress, and the instability wavenumber at the onset of the instability, is obtained by means of the Floquet theory for a general arbitrary time periodic electric field. The limit of vanishing viscosities is shown to be in excellent agreement with the marginal stability curves predicted by means of a Mathieu equation. The influence of finite viscosity and electrode separation is discussed in relation to the ideal case of inviscid fluids. The methodology to obtain the marginal stability curves developed here is applicable to any arbitrary but time periodic signal, as demonstrated for the case of a signal with two different frequencies, and four different frequencies with a dc offset. The mode coupling in the interfacial normal stress leads to appearance of harmonic and subharmonic modes, characterized by the frequency of the oscillating interface at an integral or half-integral multiple of the applied frequency, respectively. This is in contrast to the application of a voltage with a single frequency which always leads to a harmonic mode oscillation of the interface. Whether a harmonic or subharmonic mode is the most unstable one depends on details of the excitation signal.

  14. Stress, psychological distress, and coping in patients on the waiting list for lung transplantation : an exploratory study

    NARCIS (Netherlands)

    Vermeulen, KM; Bosma, OH; van der Bij, W; Koeter, GH; TenVergert, EM

    Little information is available in literature on quality of life, stress and coping during the period patients are waiting for lung transplantation. This study explored potential stressful events that patients experience during the waiting period assessed the level of anxiety and depression and

  15. Wait too long to talk about kidney disease and you could be waiting for a kidney.

    Science.gov (United States)

    ... Home Current Issue Past Issues Public Service Announcement Kidney Disease Past Issues / Summer 2006 Table of Contents ... Javascript on. Wait too long to talk about kidney disease and you could be waiting for a ...

  16. Stochastic resonance in a time-delayed asymmetric bistable system with mixed periodic signal

    International Nuclear Information System (INIS)

    Yong-Feng, Guo; Wei, Xu; Liang, Wang

    2010-01-01

    This paper studies the phenomenon of stochastic resonance in an asymmetric bistable system with time-delayed feedback and mixed periodic signal by using the theory of signal-to-noise ratio in the adiabatic limit. A general approximate Fokker–Planck equation and the expression of the signal-to-noise ratio are derived through the small time delay approximation at both fundamental harmonics and mixed harmonics. The effects of the additive noise intensity Q, multiplicative noise intensity D, static asymmetry r and delay time τ on the signal-to-noise ratio are discussed. It is found that the higher mixed harmonics and the static asymmetry r can restrain stochastic resonance, and the delay time τ can enhance stochastic resonance. Moreover, the longer the delay time τ is, the larger the additive noise intensity Q and the multiplicative noise intensity D are, when the stochastic resonance appears. (general)

  17. Stochastic model stationarization by eliminating the periodic term and its effect on time series prediction

    Science.gov (United States)

    Moeeni, Hamid; Bonakdari, Hossein; Fatemi, Seyed Ehsan

    2017-04-01

    Because time series stationarization has a key role in stochastic modeling results, three methods are analyzed in this study. The methods are seasonal differencing, seasonal standardization and spectral analysis to eliminate the periodic effect on time series stationarity. First, six time series including 4 streamflow series and 2 water temperature series are stationarized. The stochastic term for these series obtained with ARIMA is subsequently modeled. For the analysis, 9228 models are introduced. It is observed that seasonal standardization and spectral analysis eliminate the periodic term completely, while seasonal differencing maintains seasonal correlation structures. The obtained results indicate that all three methods present acceptable performance overall. However, model accuracy in monthly streamflow prediction is higher with seasonal differencing than with the other two methods. Another advantage of seasonal differencing over the other methods is that the monthly streamflow is never estimated as negative. Standardization is the best method for predicting monthly water temperature although it is quite similar to seasonal differencing, while spectral analysis performed the weakest in all cases. It is concluded that for each monthly seasonal series, seasonal differencing is the best stationarization method in terms of periodic effect elimination. Moreover, the monthly water temperature is predicted with more accuracy than monthly streamflow. The criteria of the average stochastic term divided by the amplitude of the periodic term obtained for monthly streamflow and monthly water temperature were 0.19 and 0.30, 0.21 and 0.13, and 0.07 and 0.04 respectively. As a result, the periodic term is more dominant than the stochastic term for water temperature in the monthly water temperature series compared to streamflow series.

  18. Primate enamel evinces long period biological timing and regulation of life history.

    Science.gov (United States)

    Bromage, Timothy G; Hogg, Russell T; Lacruz, Rodrigo S; Hou, Chen

    2012-07-21

    The factor(s) regulating the combination of traits that define the overall life history matrix of mammalian species, comprising attributes such as brain and body weight, age at sexual maturity, lifespan and others, remains a complete mystery. The principal objectives of the present research are (1) to provide evidence for a key variable effecting life history integration and (2) to provide a model for how one would go about investigating the metabolic mechanisms responsible for this rhythm. We suggest here that a biological rhythm with a period greater than the circadian rhythm is responsible for observed variation in primate life history. Evidence for this rhythm derives from studies of tooth enamel formation. Enamel contains an enigmatic periodicity in its microstructure called the striae of Retzius, which develops at species specific intervals in units of whole days. We refer to this enamel rhythm as the repeat interval (RI). For primates, we identify statistically significant relationships between RI and all common life history traits. Importantly, RI also correlates with basal and specific metabolic rates. With the exception of estrous cyclicity, all relationships share a dependence upon body mass. This dependence on body mass informs us that some aspect of metabolism is responsible for periodic energy allocations at RI timescales, regulating cell proliferation rates and growth, thus controlling the pace, patterning, and co-variation of life history traits. Estrous cyclicity relates to the long period rhythm in a body mass-independent manner. The mass-dependency and -independency of life history relationships with RI periodicity align with hypothalamic-mediated neurosecretory anterior and posterior pituitary outputs. We term this period the Havers-Halberg Oscillation (HHO), in reference to Clopton Havers, a 17th Century hard tissue anatomist, and Franz Halberg, a long-time explorer of long-period rhythms. We propose a mathematical model that may help elucidate

  19. Natural convection in square enclosure induced by inner circular cylinder with time-periodic pulsating temperature

    KAUST Repository

    Huang, Zhu

    2015-03-01

    The periodic unsteady natural convection flow and heat transfer in a square enclosure containing a concentric circular cylinder is numerically studied. The temperature of the inner circular cylinder fluctuates periodically with time at higher averaged value while the temperature of the enclosure keeps lower constant, and the natural convection is driven by the temperature difference. The two-dimensional natural convection is simulated with high accuracy temporal spectral method and local radial basis functions method. The Rayleigh number is studied in the range 103 ≤ Ra ≤ 106, the temperature pulsating period ranges from 0.01 to 100 and the temperature pulsating amplitudes are a = 0.5, 1.0 and 1.5. Numerical results reveal that the fluid flow and heat transfer is strongly dependent on the pulsating temperature of inner cylinder. Comparing with the steady state natural convection, the heat transfer is enhanced generally for the time-periodic unsteady natural convection, and the local maximum heat transfer rate is observed for Ra = 105 and 106. Moreover, the phenomenon of backward heat transfer is discussed quantitatively. Also, the influence of pulsating temperature on the unsteady fluid flow and heat transfer are discussed and analyzed.

  20. Why wait? : Organizing integrated processes in cancer care

    NARCIS (Netherlands)

    Leeftink, Anne Greetje

    2017-01-01

    The access to cancer diagnostics and cancer treatment is not the same for all types of cancer patients. Furthermore, the resources involved in these processes are costly and scarce. Long access and waiting times to diagnostics and treatment can cause increased anxiety of patients. The goal of this

  1. Tracing temperature in a nanometer size region in a picosecond time period.

    Science.gov (United States)

    Nakajima, Kaoru; Kitayama, Takumi; Hayashi, Hiroaki; Matsuda, Makoto; Sataka, Masao; Tsujimoto, Masahiko; Toulemonde, Marcel; Bouffard, Serge; Kimura, Kenji

    2015-08-21

    Irradiation of materials with either swift heavy ions or slow highly charged ions leads to ultrafast heating on a timescale of several picosecond in a region of several nanometer. This ultrafast local heating result in formation of nanostructures, which provide a number of potential applications in nanotechnologies. These nanostructures are believed to be formed when the local temperature rises beyond the melting or boiling point of the material. Conventional techniques, however, are not applicable to measure temperature in such a localized region in a short time period. Here, we propose a novel method for tracing temperature in a nanometer region in a picosecond time period by utilizing desorption of gold nanoparticles around the ion impact position. The feasibility is examined by comparing with the temperature evolution predicted by a theoretical model.

  2. The effect of rinsing time periods on wettability of elastomeric impression materials: in vitro study

    Directory of Open Access Journals (Sweden)

    Özlem Acar

    2016-01-01

    Full Text Available OBJECTIVE: The aim of this study was to determine whether different rinsing time periods affected the wettability of polymerized elastomeric impression materials. MATERIALS AND METHOD: Panasil Contact Plus (PCP, Panasil Contact Non-Surfactant (PCNS, Panasil Initial Contact (PIC, Express (EXP and Impregum (IMP impression materials were tested. Standardized samples were rinsed with water for 10 s, 15 s or 20 s, and the wettability was determined by contact angle measurement through an evaluation period of 60 seconds (n=7. Non-rinsed groups were used as control. Measurements were made at 5 time points (at 0, 6, 15, 30 and 60 seconds. Kruskal Wallis test and Conover’s multiple comparison tests were used for all multiple comparisons. Bonferroni adjustment was applied for controlling Type I error (p0.002. CONCLUSION: Rinsing the surfactant-containing polyvinylsiloxane impression materials decreased their wettability, whereas no such effect was seen for the surfactant free polyvinylsiloxane and polyether impression materials.

  3. Periodic solution for state-dependent impulsive shunting inhibitory CNNs with time-varying delays.

    Science.gov (United States)

    Şaylı, Mustafa; Yılmaz, Enes

    2015-08-01

    In this paper, we consider existence and global exponential stability of periodic solution for state-dependent impulsive shunting inhibitory cellular neural networks with time-varying delays. By means of B-equivalence method, we reduce these state-dependent impulsive neural networks system to an equivalent fix time impulsive neural networks system. Further, by using Mawhin's continuation theorem of coincide degree theory and employing a suitable Lyapunov function some new sufficient conditions for existence and global exponential stability of periodic solution are obtained. Previous results are improved and extended. Finally, we give an illustrative example with numerical simulations to demonstrate the effectiveness of our theoretical results. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Mimicking Nonequilibrium Steady States with Time-Periodic Driving (Open Source)

    Science.gov (United States)

    2016-05-18

    construction does not require the solution of any differential equations , only linear algebraic equations . By contrast, a mapping in the opposite...set of algebraic linear equations . The mapping between NESS and SP presented above was not intended as a set of operational instructions for... differential equations with time-periodic parameters. Typically, this can only be done numerically. In some applications, transition rates are constrained by

  5. ANALYSIS OF RELIABILITY OF THE PERIODICALLY AND CONTINUOUSLY CONTROLLED QUEUING SYSTEM WITH TIME REDUNDANCY

    International Nuclear Information System (INIS)

    Mikadze, I.; Namchevadze, T.; Gobiani, I.

    2007-01-01

    There is proposed a generalized mathematical model of the queuing system with time redundancy without preliminary checking of the queuing system at transition from the free state into the engaged one. The model accounts for various failures of the queuing system detected by continuous instrument control, periodic control, control during recovery and the failures revealed immediately after accumulation of a certain number of failures. The generating function of queue length in both stationary and nonstationary modes was determined. (author)

  6. Timing of millennial-scale climate change in Antarctica and Greenland during the last glacial period

    DEFF Research Database (Denmark)

    Blunier, T; Brook, E J

    2001-01-01

    A precise relative chronology for Greenland and West Antarctic paleotemperature is extended to 90,000 years ago, based on correlation of atmospheric methane records from the Greenland Ice Sheet Project 2 and Byrd ice cores. Over this period, the onset of seven major millennial-scale warmings in A....... This pattern provides further evidence for the operation of a "bipolar see-saw" in air temperatures and an oceanic teleconnection between the hemispheres on millennial time scales....

  7. Numerical detection of unstable periodic orbits in continuous-time dynamical systems with chaotic behaviors

    Directory of Open Access Journals (Sweden)

    Y. Saiki

    2007-09-01

    Full Text Available An infinite number of unstable periodic orbits (UPOs are embedded in a chaotic system which models some complex phenomenon. Several algorithms which extract UPOs numerically from continuous-time chaotic systems have been proposed. In this article the damped Newton-Raphson-Mees algorithm is reviewed, and some important techniques and remarks concerning the practical numerical computations are exemplified by employing the Lorenz system.

  8. Period-doubling bifurcation and chaos control in a discrete-time mosquito model

    Directory of Open Access Journals (Sweden)

    Qamar Din

    2017-12-01

    Full Text Available This article deals with the study of some qualitative properties of a discrete-time mosquito Model. It is shown that there exists period-doubling bifurcation for wide range of bifurcation parameter for the unique positive steady-state of given system. In order to control the bifurcation we introduced a feedback strategy. For further confirmation of complexity and chaotic behavior largest Lyapunov exponents are plotted.

  9. Time-varying singular value decomposition for periodic transient identification in bearing fault diagnosis

    Science.gov (United States)

    Zhang, Shangbin; Lu, Siliang; He, Qingbo; Kong, Fanrang

    2016-09-01

    For rotating machines, the defective faults of bearings generally are represented as periodic transient impulses in acquired signals. The extraction of transient features from signals has been a key issue for fault diagnosis. However, the background noise reduces identification performance of periodic faults in practice. This paper proposes a time-varying singular value decomposition (TSVD) method to enhance the identification of periodic faults. The proposed method is inspired by the sliding window method. By applying singular value decomposition (SVD) to the signal under a sliding window, we can obtain a time-varying singular value matrix (TSVM). Each column in the TSVM is occupied by the singular values of the corresponding sliding window, and each row represents the intrinsic structure of the raw signal, namely time-singular-value-sequence (TSVS). Theoretical and experimental analyses show that the frequency of TSVS is exactly twice that of the corresponding intrinsic structure. Moreover, the signal-to-noise ratio (SNR) of TSVS is improved significantly in comparison with the raw signal. The proposed method takes advantages of the TSVS in noise suppression and feature extraction to enhance fault frequency for diagnosis. The effectiveness of the TSVD is verified by means of simulation studies and applications to diagnosis of bearing faults. Results indicate that the proposed method is superior to traditional methods for bearing fault diagnosis.

  10. Algorithm for determining two-periodic steady-states in AC machines directly in time domain

    Directory of Open Access Journals (Sweden)

    Sobczyk Tadeusz J.

    2016-09-01

    Full Text Available This paper describes an algorithm for finding steady states in AC machines for the cases of their two-periodic nature. The algorithm enables to specify the steady-state solution identified directly in time domain despite of the fact that two-periodic waveforms are not repeated in any finite time interval. The basis for such an algorithm is a discrete differential operator that specifies the temporary values of the derivative of the two-periodic function in the selected set of points on the basis of the values of that function in the same set of points. It allows to develop algebraic equations defining the steady state solution reached in a chosen point set for the nonlinear differential equations describing the AC machines when electrical and mechanical equations should be solved together. That set of those values allows determining the steady state solution at any time instant up to infinity. The algorithm described in this paper is competitive with respect to the one known in literature an approach based on the harmonic balance method operated in frequency domain.

  11. Improved long-term outcomes after resection of pancreatic adenocarcinoma: a comparison between two time periods.

    Science.gov (United States)

    Serrano, Pablo E; Cleary, Sean P; Dhani, Neesha; Kim, Peter T W; Greig, Paul D; Leung, Kenneth; Moulton, Carol-Anne; Gallinger, Steven; Wei, Alice C

    2015-04-01

    Despite reduced perioperative mortality and routine use of adjuvant therapy following pancreatectomy for pancreatic ductal adenocarcinoma (PDAC), improvement in long-term outcome has been difficult to ascertain. This study compares outcomes in patients undergoing resection for PDAC within a single, high-volume academic institution over two sequential time periods. Retrospective review of patients with resected PDAC, in two cohorts: period 1 (P1), 1991-2000; and period 2 (P2), 2001-2010. Univariate and multivariate analyses using the Cox proportional hazards model were performed to determine prognostic factors associated with long-term survival. Survival was evaluated using Kaplan-Meier analyses. A total of 179 pancreatectomies were performed during P1 and 310 during P2. Perioperative mortality was 6.7 % (12/179) in P1 and 1.6 % (5/310) in P2 (p = 0.003). P2 had a greater number of lymph nodes resected (17 [0-50] vs. 7 [0-31]; p P2 (p P2 (p < 0.001). Factors associated with improved long-term survival remain comparable over time. Short- and long-term survival for patients with resected PDAC has improved over time due to decreased perioperative mortality and increased use of adjuvant therapy, although the proportion of 5-year survivors remains small.

  12. Evaluation of 'period-generated' control laws for the time-optimal control of reactor power

    International Nuclear Information System (INIS)

    Bernard, J.A.

    1988-01-01

    Time-Optimal control of neutronic power has recently been achieved by developing control laws that determine the actuator mechanism velocity necessary to produce a specified reactor period. These laws are designated as the 'MIT-SNL Period-Generated Minimum Time Control Laws'. Relative to time-optimal response, they function by altering the rate of change of reactivity so that the instantaneous period is stepped from infinity to its minimum allowed value, held at that value until the desired power level is attained, and then stepped back to infinity. The results of a systematic evaluation of these laws are presented. The behavior of each term in the control laws is shown and the capability of these laws to control properly the reactor power is demonstrated. Factors affecting the implementation of these laws, such as the prompt neutron lifetime and the differential reactivity worth of the actuators, are discussed. Finally, the results of an experimental study in which these laws were used to adjust the power of the 5 MWt MIT Research Reactor are shown. The information presented should be of interest to those designing high performance control systems for test, spacecraft, or, in certain instances, commercial reactors

  13. A technique to detect periodic and non-periodic ultra-rapid flux time variations with standard radio-astronomical data

    Science.gov (United States)

    Borra, Ermanno F.; Romney, Jonathan D.; Trottier, Eric

    2018-06-01

    We demonstrate that extremely rapid and weak periodic and non-periodic signals can easily be detected by using the autocorrelation of intensity as a function of time. We use standard radio-astronomical observations that have artificial periodic and non-periodic signals generated by the electronics of terrestrial origin. The autocorrelation detects weak signals that have small amplitudes because it averages over long integration times. Another advantage is that it allows a direct visualization of the shape of the signals, while it is difficult to see the shape with a Fourier transform. Although Fourier transforms can also detect periodic signals, a novelty of this work is that we demonstrate another major advantage of the autocorrelation, that it can detect non-periodic signals while the Fourier transform cannot. Another major novelty of our work is that we use electric fields taken in a standard format with standard instrumentation at a radio observatory and therefore no specialized instrumentation is needed. Because the electric fields are sampled every 15.625 ns, they therefore allow detection of very rapid time variations. Notwithstanding the long integration times, the autocorrelation detects very rapid intensity variations as a function of time. The autocorrelation could also detect messages from Extraterrestrial Intelligence as non-periodic signals.

  14. How tolerable is delay? : Consumers' evaluations of internet web sites after waiting

    NARCIS (Netherlands)

    B.G.C. Dellaert (Benedict); B.E. Kahn

    1998-01-01

    textabstractHow consumer's waiting times affect their retrospective evaluations of Internet Web Sites is investigated in four computer-based experiments. Results show that waiting can but does not always negatively affect evaluations of Web Sites. Results also show that the potential negative

  15. Multiresource allocation and scheduling for periodic soft real-time applications

    Science.gov (United States)

    Gopalan, Kartik; Chiueh, Tzi-cker

    2001-12-01

    Real-time applications that utilize multiple system resources, such as CPU, disks, and network links, require coordinated scheduling of these resources in order to meet their end-to-end performance requirements. Most state-of-the-art operating systems support independent resource allocation and deadline-driven scheduling but lack coordination among multiple heterogeneous resources. This paper describes the design and implementation of an Integrated Real-time Resource Scheduler (IRS) that performs coordinated allocation and scheduling of multiple heterogeneous resources on the same machine for periodic soft real-time application. The principal feature of IRS is a heuristic multi-resource allocation algorithm that reserves multiple resources for real-time applications in a manner that can maximize the number of applications admitted into the system in the long run. At run-time, a global scheduler dispatches the tasks of the soft real-time application to individual resource schedulers according to the precedence constraints between tasks. The individual resource schedulers, which could be any deadline based schedulers, can make scheduling decisions locally and yet collectively satisfy a real-time application's performance requirements. The tightness of overall timing guarantees is ultimately determined by the properties of individual resource schedulers. However, IRS maximizes overall system resource utilization efficiency by coordinating deadline assignment across multiple tasks in a soft real-time application.

  16. Self-publishing of Lithuanian cultural periodicals in Soviet and contemporary times

    Directory of Open Access Journals (Sweden)

    Asta Urbanaviciute

    2015-07-01

    Full Text Available The aim of this article is to analyse self-publishing trends of Lithuanian cultural periodicals focusing on the historical and contemporary contexts. The article provides an overview of the reasons for historical cultural periodical self-published texts, known as samizdats, to appear, as well as their publishing and circulation trends in Lithuania. It also analyses what contemporary cultural self-publishing is: whether it is a completely independent, logical consequence of the digital age, which emerged under favourable circumstances, or if it can be characterized as having something in common with the past experiences. The most active years of the periodical underground press publishing in Soviet Lithuanian self-publishing development were between 1975 and 1981. Self-published texts ideologically diverged into three main directions: religious, civic, and cultural-artistic. A total of 22 publications were being published for a longer or shorter period of time. While analysing contemporary cultural self-publishing topics, the report focuses only on online cultural texts, irrespective of the printed ones. Survey method was used to find out how much and in what aspect modern Internet users perceive historical periodical self-publishing, and how and in what aspect they value modern cultural self-published texts. The results show that 18-35-year-old respondents have not acquired the skills necessary to analyse samizdat publishing. They associate the word self-publishing with digital texts only, which due to favourable conditions spread easily through social networks and blogs. In the era of advancing computer technologies and the Internet, every person who has the time and desire may become a developer, an author, or at least a disseminator of information: this tradition is becoming more and more topical and quite frequently – an almost self-evident phenomenon.

  17. 76 FR 42471 - Premerger Notification; Reporting and Waiting Period Requirements

    Science.gov (United States)

    2011-07-19

    ... reach those Confidential Information Memoranda, as stated in Comment 1, received by ``any employee... of seeking an engagement.'' These materials are sometimes also known informally as ``bankers' books... as valuable to staff. Whether developed by a third party for the purpose of seeking an engagement or...

  18. 78 FR 10574 - Premerger Notification; Reporting and Waiting Period Requirements

    Science.gov (United States)

    2013-02-14

    ... such information and documentary material as may be necessary and appropriate to determine whether the... a request for additional information or documentary material and without an agreement in place with... ``collections of information'' to the Office of Management and Budget (``OMB'') and obtain clearance before...

  19. 78 FR 41293 - Premerger Notification; Reporting and Waiting Period Requirements

    Science.gov (United States)

    2013-07-10

    ... documentary material as may be necessary and appropriate to make that determination. In addition, Section 7A(d... of Management and Budget (``OMB'') and obtain clearance before instituting them. Such collections of... Director [of the Office of Management and Budget] shall determine whether the collection of information by...

  20. 77 FR 50057 - Premerger Notification; Reporting and Waiting Period Requirements

    Science.gov (United States)

    2012-08-20

    ... determine whether a proposed merger or acquisition may violate the antitrust laws if consummated and, when... transaction may, if consummated, violate the antitrust laws. In addition, Section 7A(d)(2) of the Act, 15 U.S... charge of the Antitrust Division of the Department of Justice (``the Assistant Attorney General...

  1. 75 FR 57109 - Premerger Notification; Reporting and Waiting Period Requirements

    Science.gov (United States)

    2010-09-17

    ... the Antitrust Division of the Department of Justice (the ``Assistant Attorney General'' or the ``Antitrust Division'') (together the ``Antitrust Agencies'' or ``Agencies'') conduct their initial review of... or acquisition may violate the antitrust laws if consummated and, when appropriate, to seek a...

  2. On an nth-order infinitesimal generator and time-dependent operator differential equation with a strongly almost periodic solution

    Directory of Open Access Journals (Sweden)

    Aribindi Satyanarayan Rao

    2002-01-01

    Full Text Available In a Banach space, if u is a Stepanov almost periodic solution of a certain nth-order infinitesimal generator and time-dependent operator differential equation with a Stepanov almost periodic forcing function, then u,u′,…,u (n−2 are all strongly almost periodic and u (n−1 is weakly almost periodic.

  3. Dynamic effective properties of heterogeneous geological formations with spherical inclusions under periodic time variations

    Science.gov (United States)

    Rabinovich, A.; Dagan, G.; Miloh, T.

    2013-04-01

    In unsteady groundwater flow (or similar processes of heat/electrical conduction), the heterogeneous medium structure is characterized by two random properties, the conductivity K and the specific storativity S. The average head field ⟨H ⟩and the associated effective properties Kef, Sef are determined for a layer with a periodic head drop between boundaries, such that H is periodic in time, and a medium made up of a matrix with a dilute concentration of spherical inclusions. In the common quasi-steady approximation, Kef is equal to the classical steady solution while Sef = SA, the arithmetic mean. We derive expressions for the frequency dependent Kef, Sef, which are generally complex, i.e., dynamic. The main result is the delineation of the ranges of the parameters: dimensionless frequency (ω) and contrasts of conductivity (κ) and storativity (s) between the matrix and the inclusions, for which dynamic effects are significant.

  4. Current density waves in open mesoscopic rings driven by time-periodic magnetic fluxes

    International Nuclear Information System (INIS)

    Yan Conghua; Wei Lianfu

    2010-01-01

    Quantum coherent transport through open mesoscopic Aharonov-Bohm rings (driven by static fluxes) have been studied extensively. Here, by using quantum waveguide theory and the Floquet theorem we investigate the quantum transport of electrons along an open mesoscopic ring threaded by a time-periodic magnetic flux. We predicate that current density waves could be excited along such an open ring. As a consequence, a net current could be generated along the lead with only one reservoir, if the lead additionally connects to such a normal-metal loop driven by the time-dependent flux. These phenomena could be explained by photon-assisted processes, due to the interaction between the transported electrons and the applied oscillating external fields. We also discuss how the time-average currents (along the ring and the lead) depend on the amplitude and frequency of the applied oscillating fluxes.

  5. Prefrontal activity during response inhibition decreases over time in the postpartum period.

    Science.gov (United States)

    Bannbers, Elin; Gingnell, Malin; Engman, Jonas; Morell, Arvid; Sylvén, Sara; Skalkidou, Alkistis; Kask, Kristiina; Bäckström, Torbjörn; Wikström, Johan; Poromaa, Inger Sundström

    2013-03-15

    The postpartum period is characterized by complex hormonal changes, but human imaging studies in the postpartum period have thus far predominantly focused on the neural correlates of maternal behavior or postpartum depression, whereas longitudinal studies on neural correlates of cognitive function across the postpartum period in healthy women are lacking. The aim of this study was to longitudinally examine response inhibition, as a measure of executive function, during the postpartum period and its neural correlates in healthy postpartum women and non-postpartum controls. Thirteen healthy postpartum women underwent event-related functional magnetic resonance imaging while performing a Go/NoGo task. The first assessment was made within 48 h of delivery, and the second at 4-7 weeks postpartum. In addition, 13 healthy women examined twice during the menstrual cycle were included as non-postpartum controls. In postpartum women region of interest analyses revealed task-related decreased activations in the right inferior frontal gyrus, right anterior cingulate, and bilateral precentral gyri at the late postpartum assessment. Generally, postpartum women displayed lower activity during response inhibition in the bilateral inferior frontal gyri and precentral gyri compared to non-postpartum controls. No differences in performance on the Go/NoGo task were found between time-points or between groups. In conclusion, this study has discovered that brain activity in prefrontal areas during a response inhibition task decreases throughout the course of the first postpartum weeks and is lower than in non-postpartum controls. Further studies on the normal adaptive brain activity changes that occur during the postpartum period are warranted. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Identifying Time Periods of Minimal Thermal Gradient for Temperature-Driven Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    John Reilly

    2018-03-01

    Full Text Available Temperature changes play a large role in the day to day structural behavior of structures, but a smaller direct role in most contemporary Structural Health Monitoring (SHM analyses. Temperature-Driven SHM will consider temperature as the principal driving force in SHM, relating a measurable input temperature to measurable output generalized strain (strain, curvature, etc. and generalized displacement (deflection, rotation, etc. to create three-dimensional signatures descriptive of the structural behavior. Identifying time periods of minimal thermal gradient provides the foundation for the formulation of the temperature–deformation–displacement model. Thermal gradients in a structure can cause curvature in multiple directions, as well as non-linear strain and stress distributions within the cross-sections, which significantly complicates data analysis and interpretation, distorts the signatures, and may lead to unreliable conclusions regarding structural behavior and condition. These adverse effects can be minimized if the signatures are evaluated at times when thermal gradients in the structure are minimal. This paper proposes two classes of methods based on the following two metrics: (i the range of raw temperatures on the structure, and (ii the distribution of the local thermal gradients, for identifying time periods of minimal thermal gradient on a structure with the ability to vary the tolerance of acceptable thermal gradients. The methods are tested and validated with data collected from the Streicker Bridge on campus at Princeton University.

  7. Identifying Time Periods of Minimal Thermal Gradient for Temperature-Driven Structural Health Monitoring.

    Science.gov (United States)

    Reilly, John; Glisic, Branko

    2018-03-01

    Temperature changes play a large role in the day to day structural behavior of structures, but a smaller direct role in most contemporary Structural Health Monitoring (SHM) analyses. Temperature-Driven SHM will consider temperature as the principal driving force in SHM, relating a measurable input temperature to measurable output generalized strain (strain, curvature, etc.) and generalized displacement (deflection, rotation, etc.) to create three-dimensional signatures descriptive of the structural behavior. Identifying time periods of minimal thermal gradient provides the foundation for the formulation of the temperature-deformation-displacement model. Thermal gradients in a structure can cause curvature in multiple directions, as well as non-linear strain and stress distributions within the cross-sections, which significantly complicates data analysis and interpretation, distorts the signatures, and may lead to unreliable conclusions regarding structural behavior and condition. These adverse effects can be minimized if the signatures are evaluated at times when thermal gradients in the structure are minimal. This paper proposes two classes of methods based on the following two metrics: (i) the range of raw temperatures on the structure, and (ii) the distribution of the local thermal gradients, for identifying time periods of minimal thermal gradient on a structure with the ability to vary the tolerance of acceptable thermal gradients. The methods are tested and validated with data collected from the Streicker Bridge on campus at Princeton University.

  8. Variation of Time Domain Failure Probabilities of Jack-up with Wave Return Periods

    Science.gov (United States)

    Idris, Ahmad; Harahap, Indra S. H.; Ali, Montassir Osman Ahmed

    2018-04-01

    This study evaluated failure probabilities of jack up units on the framework of time dependent reliability analysis using uncertainty from different sea states representing different return period of the design wave. Surface elevation for each sea state was represented by Karhunen-Loeve expansion method using the eigenfunctions of prolate spheroidal wave functions in order to obtain the wave load. The stochastic wave load was propagated on a simplified jack up model developed in commercial software to obtain the structural response due to the wave loading. Analysis of the stochastic response to determine the failure probability in excessive deck displacement in the framework of time dependent reliability analysis was performed by developing Matlab codes in a personal computer. Results from the study indicated that the failure probability increases with increase in the severity of the sea state representing a longer return period. Although the results obtained are in agreement with the results of a study of similar jack up model using time independent method at higher values of maximum allowable deck displacement, it is in contrast at lower values of the criteria where the study reported that failure probability decreases with increase in the severity of the sea state.

  9. Summary of the CDFE nuclear data activity for 2011 - 2012 period of time, Progress report

    International Nuclear Information System (INIS)

    Varlamov, V.V.; Komarov, S.Yu.; Peskov, N.N.; Stepanov, M.E.

    2012-01-01

    This report contains the short review of the main fields of nuclear data activity of the Centre for Photonuclear Experiments Data (Centr Dannykh Fotoyadernykh Eksperimentov - CDFE) of Skobeltsyn Institute of Nuclear Physics of Lomonosov Moscow State University and main results obtained. All works were carried out in close co-operation with the Nuclear Science Section in the frame of the IAEA Nuclear Reaction Data Centres Network for the period of time from the IAEA Technical Meeting on the International Network of Nuclear Reaction Data Centers' (23 - 24 May 2011, IAEA, Vienna, Austria) till the spring of 2012. (author)

  10. The Iterative Solution to Discrete-Time H∞ Control Problems for Periodic Systems

    Directory of Open Access Journals (Sweden)

    Ivan G. Ivanov

    2016-03-01

    Full Text Available This paper addresses the problem of solving discrete-time H ∞ control problems for periodic systems. The approach for solving such a type of equations is well known in the literature. However, the focus of our research is set on the numerical computation of the stabilizing solution. In particular, two effective methods for practical realization of the known iterative processes are described. Furthermore, a new iterative approach is investigated and applied. On the basis of numerical experiments, we compare the presented methods. A major conclusion is that the new iterative approach is faster than rest of the methods and it uses less RAM memory than other methods.

  11. Dynamical stability for finite quantum spin chains against a time-periodic inhomogeneous perturbation

    International Nuclear Information System (INIS)

    Kudo, Kazue; Nakamura, Katsuhiro

    2009-01-01

    We investigate dynamical stability of the ground state against a time-periodic and spatially-inhomogeneous magnetic field for finite quantum XXZ spin chains. We use the survival probability as a measure of stability and demonstrate that it decays as P(t) ∝ t -1/2 under a certain condition. The dynamical properties should also be related to the level statistics of the XXZ spin chains with a constant spatially-inhomogeneous magnetic field. The level statistics depends on the anisotropy parameter and the field strength. We show how the survival probability depends on the anisotropy parameter, the strength and frequency of the field.

  12. Time series modelling of increased soil temperature anomalies during long period

    Science.gov (United States)

    Shirvani, Amin; Moradi, Farzad; Moosavi, Ali Akbar

    2015-10-01

    Soil temperature just beneath the soil surface is highly dynamic and has a direct impact on plant seed germination and is probably the most distinct and recognisable factor governing emergence. Autoregressive integrated moving average as a stochastic model was developed to predict the weekly soil temperature anomalies at 10 cm depth, one of the most important soil parameters. The weekly soil temperature anomalies for the periods of January1986-December 2011 and January 2012-December 2013 were taken into consideration to construct and test autoregressive integrated moving average models. The proposed model autoregressive integrated moving average (2,1,1) had a minimum value of Akaike information criterion and its estimated coefficients were different from zero at 5% significance level. The prediction of the weekly soil temperature anomalies during the test period using this proposed model indicated a high correlation coefficient between the observed and predicted data - that was 0.99 for lead time 1 week. Linear trend analysis indicated that the soil temperature anomalies warmed up significantly by 1.8°C during the period of 1986-2011.

  13. Detection of Quasi-Periodic Pulsations in Solar EUV Time Series

    Science.gov (United States)

    Dominique, M.; Zhukov, A. N.; Dolla, L.; Inglis, A.; Lapenta, G.

    2018-04-01

    Quasi-periodic pulsations (QPPs) are intrinsically connected to the mechanism of solar flares. They are regularly observed in the impulsive phase of flares since the 1970s. In the past years, the studies of QPPs regained interest with the advent of a new generation of soft X-ray/extreme ultraviolet radiometers that pave the way for statistical surveys. Since the amplitude of QPPs in these wavelengths is rather small, detecting them implies that the overall trend of the time series needs to be removed before applying any Fourier or wavelet transform. This detrending process is known to produce artificial detection of periods that must then be distinguished from real ones. In this paper, we propose a set of criteria to help identify real periods and discard artifacts. We apply these criteria to data taken by the Extreme Ultraviolet Variability Experiment (EVE)/ESP onboard the Solar Dynamics Observatory (SDO) and the Large Yield Radiometer (LYRA) onboard the PRoject for On-Board Autonomy 2 (PROBA2) to search for QPPs in flares stronger than M5.0 that occurred during Solar Cycle 24.

  14. Built spaces and features associated with user satisfaction in maternity waiting homes in Malawi.

    Science.gov (United States)

    McIntosh, Nathalie; Gruits, Patricia; Oppel, Eva; Shao, Amie

    2018-07-01

    To assess satisfaction with maternity waiting home built spaces and features in women who are at risk for underutilizing maternity waiting homes (i.e. residential facilities that temporarily house near-term pregnant mothers close to healthcare facilities that provide obstetrical care). Specifically we wanted to answer the questions: (1) Are built spaces and features associated with maternity waiting home user satisfaction? (2) Can built spaces and features designed to improve hygiene, comfort, privacy and function improve maternity waiting home user satisfaction? And (3) Which built spaces and features are most important for maternity waiting home user satisfaction? A cross-sectional study comparing satisfaction with standard and non-standard maternity waiting home designs. Between December 2016 and February 2017 we surveyed expectant mothers at two maternity waiting homes that differed in their design of built spaces and features. We used bivariate analyses to assess if built spaces and features were associated with satisfaction. We compared ratings of built spaces and features between the two maternity waiting homes using chi-squares and t-tests to assess if design features to improve hygiene, comfort, privacy and function were associated with higher satisfaction. We used exploratory robust regression analysis to examine the relationship between built spaces and features and maternity waiting home satisfaction. Two maternity waiting homes in Malawi, one that incorporated non-standardized design features to improve hygiene, comfort, privacy, and function (Kasungu maternity waiting home) and the other that had a standard maternity waiting home design (Dowa maternity waiting home). 322 expectant mothers at risk for underutilizing maternity waiting homes (i.e. first-time mothers and those with no pregnancy risk factors) who had stayed at the Kasungu or Dowa maternity waiting homes. There were significant differences in ratings of built spaces and features between the

  15. Prompt-period measurement of the Annular Core Research Reactor prompt neutron generation time

    International Nuclear Information System (INIS)

    Coats, R.L.; Talley, D.G.; Trowbridge, F.R.

    1994-07-01

    The prompt neutron generation time for the Annular Core Research Reactor was experimentally determined using a prompt-period technique. The resultant value of 25.5 μs agreed well with the analytically determined value of 24 μs. The three different methods of reactivity insertion determination yielded ±5% agreement in the experimental values of the prompt neutron generation time. Discrepancies observed in reactivity insertion values determined by the three methods used (transient rod position, relative delayed critical control rod positions, and relative transient rod and control rod positions) were investigated to a limited extent. Rod-shadowing and low power fuel/coolant heat-up were addressed as possible causes of the discrepancies

  16. Evaluation of cytotoxicity and degree of conversion of orthodontic adhesives over different time periods

    Directory of Open Access Journals (Sweden)

    Matheus Melo Pithon

    2010-06-01

    Full Text Available As new orthodontic resin adhesives continue to be marketed, rapid and sensitive tests for examining their toxic effects at the ' cell and tissue level ' are needed because patient safety has been identifi ed as a legal concept. The objective of the present study was to evaluate the cytotoxicity and degree of monomer conversion of orthodontic adhesives over different time periods. Seven adhesives: Transbond® XT, Transbond® Color Change, Quick Cure, EagleBond, Orthobond®, Fill Mágic® and Biofix® were evaluated for their cytotoxicity in L929 fibroblastic cells and for their degree of monomer conversion over different time periods. Three control groups were also analysed: Positive control (C+, consisting of Tween 80 cell detergent; Negative control (C-, consisting of PBS; and cell control (CC, consisting of cells exposed to any material. The dye-uptake technique that involves the absorption of a neutral red dye in viable cells was used for the cytotoxicity evaluation and the degree of conversion was evaluated using spectroscopy with infrared. The results showed the cytotoxicity of the adhesives at 24, 48, 72 and 168 hours. At these times, the viability values presented for these materials were statistically different from the groups CC and C- (p 0.05. In the monomer conversions there was a percentage increase of monomer conversion from 24 to 72 hours. A direct correlation could be observed between cytotoxicity and monomer conversions. From this work it can be concluded that all adhesives evaluated are cytotoxic at the times of 24, 48 and 72 hours. Monomers continued conversion even after photopolymerization had stopped.

  17. Prediction of in-service time period of three differently stabilized single base propellants

    Energy Technology Data Exchange (ETDEWEB)

    Bohn, Manfred A. [Fraunhofer-Institut fuer Chemische Technologie (ICT), Pfinztal-Berghausen (Germany)

    2009-06-15

    Three nitrocellulose-based propellants for use in micro gas generators equipped with different stabilizing systems have been investigated to assess the stabilization capability with regard to in-service time, whereby strong time-temperature profiles have been applied. The three stabilizing systems have been (i) 0.74 mass-% diphenylamine (DPA) and 0.48 mass-% Akardite II (Ak II); (ii) 1.25 mass-% Ak II; (iii) 2.04 mass-% Ak II. Several profiles were considered. Two simulate the heating at sun exposure in hot areas, others consider environmental temperatures in hot-humid and hot-dry areas. They were evaluated according to the load and finally one was chosen for the assessment. The contents of stabilizers were determined by high performance liquid chromatography after Soxhlet type extraction. To describe stabilizer consumption, the most suitable kinetic model was taken. Therewith a prediction was made using the chosen time-temperature profile named 'Phoenix', designed for temperatures at the steering wheel. The objective was to reach with this profile 15 years until the consumption of primary stabilizer content. This is conservative, because with the stabilizing action of the consecutive products of the stabilizers longer times are possible. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  18. Measuring border delay and crossing times at the US-Mexico border : part II. Step-by-step guidelines for implementing a radio frequency identification (RFID) system to measure border crossing and wait times.

    Science.gov (United States)

    2012-06-01

    The purpose of these step-by-step guidelines is to assist in planning, designing, and deploying a system that uses radio frequency identification (RFID) technology to measure the time needed for commercial vehicles to complete the northbound border c...

  19. Evolution of illustrations in anatomy: a study from the classical period in Europe to modern times.

    Science.gov (United States)

    Ghosh, Sanjib Kumar

    2015-01-01

    Illustrations constitute an essential element of learning anatomy in modern times. However it required a significant evolutionary process spread over centuries, for illustrations to achieve the present status in the subject of anatomy. This review article attempts to outline the evolutionary process by highlighting on the works of esteemed anatomists in a chronological manner. Available literature suggests that illustrations were not used in anatomy during the classical period when the subject was dominated by the descriptive text of Galen. Guido da Vigevano was first to use illustrations in anatomy during the Late Middle Ages and this concept developed further during the Renaissance period when Andreas Vesalius pioneered in illustrations becoming an indispensable tool in conveying anatomical details. Toward later stages of the Renaissance period, Fabricius ab Aquapendente endeavored to restrict dramatization of anatomical illustrations which was a prevalent trend in early Renaissance. During the 18th century, anatomical artwork was characterized by the individual styles of prominent anatomists leading to suppression of anatomical details. In the 19th century, Henry Gray used illustrations in his anatomical masterpiece that focused on depicting anatomical structures and were free from any artistic style. From early part of the 20th century medical images and photographs started to complement traditional handmade anatomical illustrations. Computer technology and advanced software systems played a key role in the evolution of anatomical illustrations during the late 20th century resulting in new generation 3D image datasets that are being used in the 21st century in innovative formats for teaching and learning anatomy. © 2014 American Association of Anatomists.

  20. Development of potential map for landslides by comparing instability indices of various time periods

    Science.gov (United States)

    Chiang, Jie-Lun; Tian, Yu-Qing; Chen, Yie-Ruey; Tsai, Kuang-Jung

    2017-04-01

    In recent years, extreme rainfall events occur frequently and induced serious landslides and debris flow disasters in Taiwan. The instability indices will differ when using landslide maps of different time periods. We analyzed the landslide records during the period year, 2008 2012, the landslide area contributed 0.42% 2.94% of the total watershed area, the 2.94% was caused by the typhoon Morakot in August, 2009, which brought massive rainfall in which the cumulative maximum rainfall was up to 2900 mm. We analyzed the instability factors including elevation, slope, aspect, soil, and geology. And comparing the instability indices by using individual landslide map of 2008 2012, the landslide maps of the union of the five years, and interaction of the five years. The landslide area from union of the five years contributed 3.71%,the landslide area from interaction of the five years contributed 0.14%. In this study, Kriging was used to establish the susceptibility map in selected watershed. From interaction of the five years, we found the instability index above 4.3 can correspond to those landslide records. The potential landslide area of the selected watershed, where collapses occur more likely, belongs to high level and medium-high level; the area is 13.43% and 3.04% respectively.