Multi-parameter predictive shift schedule of automatic mechanical transmission for electric bus

Shift schedule is crucial in improving the dynamic and economic performance of electric vehicles (EVs) equipped with automatic mechanical transmission (AMT). As the driver, vehicle, and road constitute a closed-loop inseparable system, identifying the states of both vehicle and road is fundamental to realizing optimal shift schedule. However, the existing shift strategies neglect the coupling relationship of multiple parameters to the shift strategy. To minimize this gap, this paper presents a novel multi-parameter shift schedule based on model predictive control. Firstly, cubature Kalman filters (CKF) algorithm is employed to accurately estimate vehicle quality and road slope, which could improve the energy economy of EVs. Secondly, an artificial neural network (ANN) is adopted to forecast the compound future short horizon driving conditions, which contains the perdition information of vehicle velocity and road slope. Meanwhile, the AMT predictive shift schedule based on the above estimated and forecast information is constructed, which used dynamic programming to optimize in the rolling horizon. Simulation study results indicate that the ANN-based predictive approach shows better performance on accuracy and robustness than that of Markov chain, and the electricity consumption over China typical urban driving cycle (CTUDC) is further reduced by 6.79% than that of multi-parameter rule-based shift schedule.

The Optimization between Physician Satisfaction and Hospital Profit in Cross-Hospital Scheduling—A Case Study of Some Hospitals in Taiwan

In recent years, the majority of the population has preferred to go to large hospitals regardless of the severity of their illnesses, resulting in a waste of medical resources. In view of this situation, the government has proposed a cross-hospital integration plan to promote the integration of medical resources. Hospitals that provide support can not only increase their income but also extend their medical coverage to other regions and get wide access to more patients. While previous studies mainly focused on the internal shift scheduling of hospitals, this study took into account both the internal hospital and the support to branch hospitals and particularly explored the financial benefits generated by the provision of support and the satisfaction of physicians on shift scheduling. Decision makers can give different weight values according to the management needs and then determine the most appropriate physician shift schedule according to the final decision value. The shift-schedule-building system developed in this study could be used to quickly calculate the most appropriate shift schedule according to the actual needs, which could replace the time-consuming method of manual scheduling and improve physician satisfaction and hospital financial income.

Transmission ratio optimization of two-speed gearbox in battery electric passenger vehicles

To optimize the power and economic performance of battery electric passenger vehicles, an 8.5-m-long battery electric passenger vehicle was selected as the research subject. The simulated-annealing particle-swarm-optimization (SAPSO) algorithm was applied to optimize the two-speed gearbox and transmission ratio of the vehicle. With the opening of the accelerator pedal and speed as variables, a comprehensive gear shift schedule that considered both the power and economic performance was established. The comprehensive gear shift schedule curve was defined in the model built in the ADVISOR software. The transmission ratio was jointly optimized using the ADVISOR and ISIGHT software, and then the ADVISOR simulation software was used to analyze the economic and dynamic performances corresponding to the optimized transmission ratio. Finally, we compared the power and economic performances of the vehicle before and after transmission ratio optimization, the results of which showed that after the optimization, the maximum speed, climbing gradient, and 0–50 km/h acceleration time of the vehicle were greatly improved, and the driving range was slightly shortened. This enabled performance advantages of the battery electric passenger vehicle by balancing the power and economic performances of the vehicle.

784 Naturalistic Measurement of Sleep/Wake Disturbance in Adults Receiving Methadone Treatment for Opioid Use Disorder

Introduction Individuals with opioid use disorder (OUD) report significant sleep/wake disturbance, which continues even after stabilization on medication-assisted treatment (MAT). However, the nature of sleep/wake disturbance in this population has not been well documented objectively. Here we analyze naturalistic wrist actigraphy recordings in individuals with OUD receiving methadone-based MAT. Methods Seven adults undergoing methadone treatment for OUD (ages 26–50; 4 women) wore a wrist actigraph (Actiwatch-2, Philips Respironics) continuously for 7 days. They were asked to adhere to their normal sleep schedule in order to obtain naturalistic observations. Reference data were collected in a separate study of healthy controls, in which 14 hospital nurses (ages 20–60; 13 women) wore a wrist actigraph continuously for 7 days. In this reference group, 7 participants had a day shift schedule (07:00–19:00) and 7 had a night shift schedule (19:00–07:00), with six 12h shifts in a 2-week period. Actigraphic data were collected in 1min epochs, and the sleep/wake status for each epoch was estimated using Actiware 6.0.9 (Philips Respironics). The estimated sleep/wake patterns were subjected to cosinor analysis to assess 24h rhythmicity and analysis of the distribution of inactive periods to assess sleep continuity. Results For the reference group, nurses working day shifts displayed strong 24h rhythmicity, whereas nurses working night shifts showed blunted 24h rhythmicity (F[1,12]=66.11, p<0.001). However, both day and night nurses exhibited high sleep continuity (KS test, p=0.82). By contrast, for the group with OUD receiving methadone, the strength of 24h rhythmicity was reduced to between that of the day and night shift nurses in the reference group, indicating weak regularity of sleep/wake patterns (F[2,18]=33.79, p<0.001). Furthermore, individuals with OUD receiving methadone experienced low sleep continuity compared to the reference group (KS test, p=0.030). Conclusion These naturalistic observations confirm the presence of sleep/wake disturbance, resulting from both irregular sleep/wake patterns and low sleep continuity, in individuals receiving methadone-based MAT for OUD. Sleep/wake disturbance may interfere with the ability to achieve OUD recovery goals, and comparing sleep disturbance in MAT populations to reference data highlights the need to consider sleep in these populations as a clinical priority. Support (if any) State of Washington Initiative Measure No. 171

056 Effects of Simulated Shift Schedules on Visual Search

Introduction Visual search is important in many operational tasks, such as passive sonar monitoring in naval operations. Shift work can contribute to fatigue and task performance impairment; in particular, backward rotating shift schedules have been shown to impair vigilant attention performance. However, the impact on visual search performance, above and beyond impaired vigilant attention, is unknown. We investigated the effects of two distinct shift work schedules using a visual search task with properties of real-life visual search performance. Methods N=13 adult males (ages 18–39) completed a 6-day/5-night laboratory study with an acclimation day, four simulated shift days, and a recovery day. Shift days involved either a 5h-on/15h-off backward rotating schedule (n=8) or a 3h-on/9h-off fixed schedule (n=5). The visual search task was performed once per shift at varying time of day depending on shift. Participants viewed search arrays where stimuli consisted of colored letters of different shapes. Over three trial blocks of 24 trials each, participants determined if a target was present or absent among 1, 5, 15, or 30 distractors. Similarity between targets and distractors was manipulated between blocks, such that targets differed from distractors by color only, shape only, or either color or shape but not both. For each distinct target feature block, and separately for presence or absence of a target, slopes of response times regressed against number of stimuli were calculated to quantify visual search rates. Mixed-effects ANOVA was used to analyze visual search rates by shift schedule and shift day. Results There were no significant effects of shift schedule (all p>0.30), shift day (all p>0.13), or their interaction (all p>0.22) on visual search rates. Conclusion Previous work showed degraded vigilant attention in the shift schedules considered here, especially in the backward rotating schedule, which may compromise operational performance. However, while our sample may have been too small to have adequate statistical power, we failed to identify specific impairments in visual search with statistical significance. It remains to be determined whether greater levels of fatigue, such as could be induced by total sleep deprivation, would reveal significant visual search deficits. Support (if any) Naval Postgraduate School award N62271-13-M-1228

095 Steering Wheel Angle Excursions as a Measure of Fatigue-Related Driver Performance Impairment

Introduction Fatigue from sleep loss and circadian misalignment causes automobile driving performance impairment. Metrics based on steering wheel angle, which is straightforward to measure, could be used to quantify this impairment. As the tail of the distribution of steering wheel angles (absolute magnitude of deviation from center) increases with fatigue, we investigated whether driving performance impairment could be quantified based on the prevalence of steering wheel excursions beyond a given angle threshold. We used data from two published laboratory studies of simulated shift work, in which fatigue remained low during day shifts but increased across time awake during night shifts. Methods N=37 healthy adults (ages 26.8±5.2y; 25 men) were assigned to a simulated night shift schedule (awake 20:00-10:00) or day shift schedule (awake 08:00-22:00; study 1 only). After an adaptation period, participants underwent two 5-day shift cycles with an intervening rest period. Driving performance was measured on a high-fidelity simulator during adaptation (data not used) and four times at 3h intervals during each shift day. Every drive involved 30min driving at 55mph, including ten 0.5mi uneventful straightaways being considered here. Steering wheel angle was measured at 72Hz (study 1) or 60Hz (study 2). A total of 1,471 drives (31,394,498 angle measurements) were available for analysis. Results We investigated angle thresholds across 0.01-0.25rad in 0.01rad intervals and counted the corresponding number of threshold excursions in each drive for each participant. For study 1, we applied mixed-effects ANOVA with fixed effects for condition and time awake, and their interaction, and determined the local effect size for interaction. A 0.03rad (1.7°) threshold yielded the greatest effect size, f²=0.031 (small). For this threshold, we repeated the analysis using the data from both studies, controlling for study. The interaction was significant (F[3,1428]=13.23, p<0.001), showing low driving impairment across time awake during day shifts but increasing impairment across time awake during night shifts. Conclusion The prevalence of steering wheel excursions beyond a 1.7° angle threshold yielded sensitivity to fatigue-related driving performance impairment during simulated night shifts. Further research will extend our results to driving through curves and with greater fatigue levels. Support (if any) FMCSA DTMC75-07-D-00006

Association between chronotype and psychomotor performance of rotating shift workers

It is known that the chronotype potentially mediates the performance and tolerance to work in shifts and that shift rotation is associated with negative effects on psychomotor performance. This study aimed to evaluate the effect of chronotype on psychomotor performance throughout a complete shift rotation schedule. Thirty males working in clockwise rotating shifts from a mining company were evaluated under a real-life condition over the following shift schedule: 2 days of day work, 2 days of evening work and 2 days of night work. The chronotype was determined using the Munich Chronotype Questionnaire adapted for shift workers and the obtained scores were categorized by tertiles (early-type, intermediate-type and late-type). Work performance was evaluated by Psychomotor Vigilance Test (PVT) daily just before shift starts and after shift ends. Sleep duration was evaluated by actigraphy over the whole shift. No isolated effect of the shift or interaction between shift and chronotype was found in the performance variables evaluated. A significant isolated effect of the chronotype showed that the early-type individuals had higher values of pre- and post-work Mean of Reaction Time (MRT) (308.77 ± 10.03 ms and 306.37 ± 8.53 ms, respectively) than the intermediate-type (257.61 ± 6.63 ms and 252.91 ± 5.97 ms, respectively, p < 0.001) and the late-type (273.35 ± 6.96 ms and 262.88 ± 6.05 ms, respectively, p < 0.001). In addition, late individuals presented a greater number of lapses of attention (5.00 ± 0.92; p < 0.05) than early (1.94 ± 0.50, p < 0.05) and intermediate (1.33 ± 0.30, p < 0.001) ones. We concluded that, compared with intermediates, late-type workers had a greater number of lapses of attention on the shift schedule as a whole, while early-type workers showed the highest pre- and post-work MRT. These findings show that the psychomotor performance of rotating shift workers seems to be influenced by the chronotype, but not by the shift rotation.

An Integrated Shift Schedule Assessment and Selection Procedure for Power & Water Plants in Kingdom of Bahrain

The continues increase in population and market globalization necessitated offering additional services and mass production strategy deployment. Consequently, a dramatic increase in research studies have been directed towards mitigating the shift schedule harmful physical, psychological, and social life effects on the workers. In addition, studies are currently conducted to determine the optimal shift schedule and shift rota, which is capable to incorporate human factors and applicable to the environment adopted in. In Kingdom of Bahrain there are no studies that investigate the effects of shift schedule on the operators, neither provide clear guidelines to select the appropriate shift schedule based on the environment adopted in. Accordingly, the aim of this paper is to present the development of an effective shift schedule selection mechanism that considers the physical, psychological, and social life factors for Al-Dur Power and Water Plant in Kingdom of Bahrain. The research methodology adopted was based on survey and case study. The results of this research study concluded that the shift schedule selection procedure developed was capable to involve all the stakeholders associated in the shift schedule selection process. In addition, it based the assessment and decision on the work environment adopted in.