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With the rapid increase of penetration of the wind-based resources for generating electricity, the assessment of wind potential is becoming a vital aspect more than ever. For tapping the potential for a particular wind site, in addition to precisely assessing the wind potential, the accurate forecasting of the wind speed and wind power for the different time horizons is also an important aspect. In this chapter, we discuss various aspects associated with wind power assessment. Additionally, we discuss the scale of the analysis, and the methods that have been utilized. A comprehensive view is conducted for that purpose.

Material extrusion-type fused filament fabrication (FFF) 3-D printing is a valuable tool for education. During FFF 3-D printing, thermal degradation of the polymer releases small particles and chemicals, many of which are hazardous to human health. In this study, particle and chemical emissions from 10 different filaments made from virgin (never printed) and recycled polymers were used to print the same object at the polymer manufacturer’s recommended nozzle temperature (“normal”) and at a temperature higher than recommended (“hot”) to simulate the real-world scenarios of a person intentionally or unknowingly printing on a machine with a changed setting. Emissions were evaluated in a college teaching laboratory using standard sampling and analytical methods. From mobility sizer measurements, particle number-based emission rates were 81 times higher; the proportion of ultrafine particles (diameter

Fused filament fabrication three-dimensional (FFF 3-D) printing is thought to be environmentally sustainable; however, significant amounts of waste can be generated from this technology. One way to improve its sustainability is via distributed recycling of plastics in homes, schools, and libraries to create feedstock filament for printing. Risks from exposures incurred during recycling and reuse of plastics has not been incorporated into life cycle assessments. This study characterized contaminant releases from virgin (unextruded) and recycled plastics from filament production through FFF 3-D printing. Waste polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) plastics were recycled to create filament; virgin PLA, ABS, high and low density polyethylenes, high impact polystyrene, and polypropylene pellets were also extruded into filament. The release of particles and chemicals into school classrooms was evaluated using standard industrial hygiene methodologies. All tasks released particles that contained hazardous metals (e.g., manganese) and with size capable of depositing in the gas exchange region of the lung, i.e., granulation of waste PLA and ABS (667 to 714 nm) and filament making (608 to 711 nm) and FFF 3-D printing (616 to 731 nm) with waste and virgin plastics. All tasks released vapors, including respiratory irritants and potential carcinogens (benzene and formaldehyde), mucus membrane irritants (acetone, xylenes, ethylbenzene, and methyl methacrylate), and asthmagens (styrene, multiple carbonyl compounds). These data are useful for incorporating risks of exposure to hazardous contaminants in future life cycle evaluations to demonstrate the sustainability and circular economy potential of FFF 3-D printing in distributed spaces.

Purpose – Telephone response system is the frontline of hospital operations. The purpose of this paper is to analyze a representative telephone response system of Veterans Affairs (VA) hospitals, address the existing inefficiency issues such as long call waiting time, and improve system resilience to changes. Design/methodology/approach – Resource sharing schemes are proposed to improve the system performance in answering calls related to appointment booking and medication renewal. Discrete event simulation is adopted to model the current system and the resource sharing schemes. Findings – The resource sharing schemes dramatically improve system performance reflected by the decrease of call waiting time and queue, as well as the extreme high utilization of agents in a key unit. Compared with the less desired alternative of hiring additional employees to mitigate the performance issues, the resource sharing schemes perform at par or even better. Sharing more resource during the peak hours can further balance the agent workload. Practical implications – The resource sharing schemes could alleviate staffing shortage, long waiting time, and high-abandonment rate in the bottle-beck unit of the system, and lead to better utilization of scarce resources on the hospital floor. The concept reflects localized centralization efforts in traditionally highly decentralized telephone operations in hospital systems. Originality/value – This research provides a structured approach to analyze the operations of a VA telephone response system. The developed simulation model is validated, and this provides a valuable tool for management to analyze the complicated telephone operations of the telephone systems of other VA and non-VA hospitals. Resource sharing constitutes a cost-effective solution for improving system performance and resilience.

This study focuses on experimental design-based approach for process optimisation of a custom-made digital light processing 3D printer. Output measures are developed taking precision and accuracy into consideration. Initial runs were conducted to identify the prominent factors which might play role on output measures. The results indicate that the layer thickness plays a significant role for the two of the developed output measures, photopolymerisation time for one measure, and sequence time for two measures as the interaction-effects also play a role to some. A composite figure that considers all three output measures simultaneously is also developed and a stepwise regression analysis is conducted to identify significant factors. The regression model has moderate R2 value (68.12%), also indicating that layer thickness and photopolymerisation period play a role. The recommended levels for layer thickness is found to be 0.2 millimetres and photopolymerisation period as 12 seconds based on the composite figure.

The convex recoloring (CR) problem is to recolor the nodes of a colored graph at minimum number of color changes such that each color induces a connected subgraph. We adjust to the convex recoloring problem the column generation framework developed by Johnson et al. (Math Program 62:133–151, 1993). For the convex recoloring problem on a tree, the subproblem to generate columns can be solved in polynomial time by a dynamic programming algorithm. The column generation framework solves the convex recoloring problem on a tree with a large number of colors extremely fast.

The article presents a novel quantitative methodology for wind farm management. The methodology starts by forecasting the time series mean and volatility of wind speed. The forecasting of wind speed mean and its volatility is built on an autoregressive moving average model with a generalized autoregressive conditional heteroscedasticity process, namely an ARMA-GARCH model. With the prediction of wind speed mean and its volatility, the article establishes the interval estimation of wind speed which makes the prediction of wind speed more accurate and reliable. To facilitate the quantitative management of wind farm, the operation probability (OP) of wind turbine is formulated according to the interval estimation of wind speed. Based on the characteristics power curve of wind turbine, the article develops the conditional expected wind power output equation (CEWPOE). The interval estimation of wind speed, the OP of wind turbine, and the CEWPOE thus comprise an integrated methodology for the quantitative manag...

Short-term forecasting of wind speed and direction is of great importance to wind turbine operation and efficient energy harvesting. In this study, the forecasting of wind speed and direction tuple is performed. Four approaches based on autoregressive moving average (ARMA) method are employed for this purpose. The first approach features the decomposition of the wind speed into lateral and longitudinal components. Each component is represented by an ARMA model, and the results are combined to obtain the wind direction and speed forecasts. The second approach employs two independent ARMA models – a traditional ARMA model for predicting wind speed and a linked ARMA model for wind direction. The third approach features vector autoregression (VAR) models to forecast the tuple of wind attributes. The fourth approach involves employing a restricted version of the VAR approach to predict the same. By employing these four approaches, the hourly mean wind attributes are forecasted 1-h ahead for two wind observation sites in North Dakota, USA. The results are compared using the mean absolute error (MAE) as a measure for forecasting quality. It is found that the component model is better at predicting the wind direction than the traditional-linked ARMA model, whereas the opposite is observed for wind speed forecasting. Utilizing VAR approaches rather than the univariate counterparts brings modest improvement in wind direction prediction but not in wind speed prediction. Between restricted and unrestricted versions of VAR models, there is little difference in terms of forecasting performance.

Accurately modeling the mean and volatility of wind speed can be beneficial to effective wind energy utilization. For this purpose, this paper evaluates the effectiveness of autoregressive moving average–generalized autoregressive conditional heteroscedasticity (ARMA–GARCH) approaches for modeling the mean and volatility of wind speed. Five different GARCH approaches are included, and each consists of an original form and a modified form, GARCH-in-mean (GARCH-M). As a result, 10 different model structures are evaluated, based on the 7-year hourly wind speed data collected at four different heights from an observation site in Colorado, USA. Multiple evaluation methods of modeling sufficiency are used. The results show that the ARMA–GARCH(-M) approaches can effectively catch the trend change of the mean and volatility of wind speed. Also, the volatility of wind speed has the nonlinear and asymmetric time-varying feature, and the ARMA–GARCH-M structures can consistently improve the modeling sufficiency of mean wind speed. As the height increases, the explanatory power of all ARMA–GARCH(-M) models slightly deteriorates. On the other hand, no single model structure outperforms the others at all heights, and this confirms that for any wind speed dataset, the potential models should be evaluated to find the most appropriate one for the highest modeling sufficiency.

Statistical distribution models for estimating wind energy potential spurred a great interest among researchers and practitioners recently. Bivariate statistical models for representing both wind direction and speed are helpful for the design and implementation of more efficient systems for harnessing wind energy. In this study, we construct seven different bivariate joint distributions based on three construction approaches, namely, angular-linear (AL), Farlie-Gumbel-Morgenstern (FGM) and anisotropic lognormal approaches, and then compare them using the adjusted R2 and root mean square error (RMSE) as measures of goodness of fit. For both AL and FGM approaches, the distributions of wind speed and direction need to be obtained separately before the construction of joint distribution. While using the mixture of von Mises distribution for representing the wind direction, we utilize two different mixtures of distributions for representing the wind speed, with one being the mixture of singly truncated below Normal and Weibull distribution, and the other being the mixture of three-parameter inverse Gaussian and lognormal distributions. A case study is conducted for this purpose on multiple sites in North Dakota, USA. It indicates that the two mixtures of distributions for wind speed have comparable performances. Meanwhile, there is little difference in terms of adjusted R2 and RMSE values in modelling wind direction with AL and FGM approaches. Although the anisotropic approach significantly lags behind AL and FGM approaches, the adjusted R2 and RMSE values provided by the latter two approaches are comparable. Copyright © 2010 John Wiley & Sons, Ltd

Wind speed forecasting is critical for the operations of wind turbine and penetration of wind energy into electricity systems. In this paper, a novel time series forecasting method is proposed for this purpose. This method originates from TK (Taylor Kriging) model, but is properly modified for the forecasting of wind speed time series. To investigate the performance of this new method, the wind speed data from an observation site in North Dakota, USA, are adopted. One-year hourly wind speed data are divided into 10 samples, and forecast is made for each sample. In the case study, both the modified TK method and (ARIMA) autoregressive integrated moving average method are employed and their performances are compared. It is found that on average, the proposed method outperforms the ARIMA method by 18.60% and 15.23% in terms of (MAE) mean absolute error and (RMSE) root mean square error. Meanwhile, further theoretical analysis is provided to discuss why the modified TK method is potentially more accurate than the ARIMA method for wind speed time series prediction.

Accurate analysis of long term wind data is critical to the estimation of wind energy potential for a candidate location and its nearby area. Investigating the wind speed distribution is one critical task for this purpose. This paper presents a comprehensive evaluation on probability density functions for the wind speed data from five representative sites in North Dakota. Besides the popular Weibull and Rayleigh distributions, we also include other distributions such as gamma, lognormal, inverse Gaussian, and maximum entropy principle (MEP) derived probability density functions (PDFs). Six goodness-of-fit (GOF) statistics are used to determine the appropriate distributions for the wind speed data for each site. It is found that no particular distribution outperforms others for all five sites, while Rayleigh distribution performs poorly for most of the sites. Similar to other models, the performances of MEP-derived PDFs in fitting wind speed data varies from site to site. Also, the results demonstrate that MEP-derived PDFs are flexible and have the potential to capture other possible distribution patterns of wind speed data. Meanwhile, different GOF statistics may generate inconsistent ranking orders of fit performance among the candidate PDFs. In addition, one comprehensive metric that combines all individual statistics is proposed to rank the overall performance for the chosen statistical distributions.

The telephone systems in healthcare settings serve as a viable tool for improving the quality of service provided to patients, decreasing the cost, and improving the patient satisfaction. It can play a pivotal role for transformation of the healthcare delivery for embracing personalized and patient centered care. This chapter presents a systematic review of new developments of healthcare telephone system operations in various areas such as tele-health. Current research on topics such as tele-diagnosis, tele-nursing, tele-consultation is outlined. Specific issues associated with the emerging applications such as underreferral, legal issues, patient acceptance, on-call physician are discussed. Meanwhile, the architecture and underlying technologies for healthcare telephone systems are introduced, and the performance metrics for measuring the system operations are provided. In addition, challenges and opportunities related with improving the healthcare telephone systems are identified, and the potential opportunities of optimizing these systems are pointed out.

In this research, we apply a large-scale logistic regression analysis to assess the patient missed opportunity risks at a complex VA (US Department of Veterans Affairs) hospital in three categories, namely, no-show alone, no-show combined with late patient cancellation and no-show combined with late patient and clinic cancellations. The analysis includes unique explanatory variables related to VA patients for predicting missed opportunity risks. Furthermore, we develop two aggregated weather indices by combining many weather measures and include them as explanatory variables. The results indicate that most of the explanatory variables considered are significant factors for predicting the missed opportunity risks. Patients with afternoon appointment, higher percentage service connected, and insurance, married patients, shorter lead time and appointments with longer appointment length are consistently related to lower risks of missed opportunity. Furthermore, the VA patient-related factors and the two proposed weather indices are useful predictors for the risks of no-show and patient cancellation. More importantly, this research presents an effective procedure for VA hospitals and clinics to analyze the missed opportunity risks within the complex VA information technology system, and help them to develop proper interventions to mitigate the adverse effects caused by the missed opportunities.

In this study, we develop two ARMA-GARCH models for predicting the mean and volatility of wind speed. The first model employs the standalone ARMA-GARCH model for modeling the mean wind speed and the variance simultaneously. For the second model, in the first step, the current wind vector is decomposed into lateral and longitudinal components by using the prevailing wind direction. The mean and variance of the two components are then modeled using two separate ARMA-GARCH processes. Thereafter, the two components are combined back to form the resultant single wind vector. A large wind dataset is employed for model building and prediction so that the two approaches can be compared. It shows that the standalone ARMA-GARCH model is more accurate for predicting the wind speed, whereas the component ARMA-GARCH model performs better for predicting the wind variance.

Residential wind turbines are often accompanied by an energy storage system for the off-the-grid users, instead of the on-the-grid users, to reduce the risk of black-out. In this paper, we argue that residential wind turbines with battery energy storage could actually be beneficial to the on-the-grid users as well in terms of monetary gain from differential pricing for buying electricity from the grid and the ability to sell electricity back to the grid. We develop a mixed-integer linear programming model to maximize the profit of a residential wind turbine system while meeting the daily household electricity consumption. A case study is designed to investigate the effects of differential pricing schemes and sell-back schemes on the economic output of a 2-kW wind turbine with lithium battery storage. Overall, based on the current settings in California, a residential wind turbine with battery storage carries more economical benefits than the wind turbine alone.

Many rural Veteran patients receive healthcare services from both Veterans Affairs (VA) and non-VA providers. Effective management of dual care Veteran patients to ensure the best clinical outcomes is a VA mission. The previous VA studies indicate that coordination between VA and non-VA providers has been lacking for dual care management of Veteran patients. In this study, we propose that VA proactively shares information with non-VA providers to enhance the communication process and identify the best practices to be carried out by both VA and non-VA providers for better coordination. Structured questionnaires are designed and distributed to VA and non-VA providers to obtain their evaluations on the proposed VA proactive information sharing approaches and the best practice items for dual care management. The non-VA provider respondents largely support the proposed proactive sharing items by VA, with the lowest average score being 3.96 out of a 5.0 scale on one item. In terms of the best practice items on co-managing dual care patients, three out of five items are overall rated higher than 4.0 from both sides. A pair-wise comparison between VA and non-VA perspectives further shows that the difference in average ratings of a proposed item could be significant. For such best practice items, the implementations from both sides may not be most effective.

In healthcare industry, providers, patients, and all other stakeholders must have the right information at the right time for achieving efficient and cost effective services. Exchange of information between the heterogeneous system entities plays a critical role. Health information exchange (HIE) is not only a process of transmitting data, but also a platform for streamlining operations to improve healthcare delivery in a secure manner. In this chapter, we present a comprehensive view of electronic health record (EHR) systems and HIE by presenting their architecture, benefits, challenges, and other related issues. While providing information on the current state of EHR/HIE applications, we also discuss advanced issues and secondary uses of HIE implementations, and shed some light on the future research in this area by highlighting the challenges and potentials.

Bu çalışmada, tarihte çok önemli bir yere sahip olan on dokuzuncu yüzyıl devrinde halk edebiyatına katkıda bulunan âşıklardan yol çıkarak gelenek, etkileşim ve eğitim unsurları ele alınmıştır.Çalışmada o dönemdeki siyasî olaylar hakkında ön bilgi verilerek dönemin şartları ortaya konulmuş, daha sonra ise siyasî olaylardan sosyal yaşamın nasıl etkilendiği ve Anadolu halkının o dönemdeki durumu hakkında bilgi verilmeye çalışılmıştır. Dönemin siyasî ve sosyal şartları anlatıldıktan sonra ise on dokuzuncu yüzyılda halk edebiyatının durumu ve bu yüzyıla damgasını vuran önemli âşıklar ve eserleri verilmiştir. Tüm bu bilgiler ışığında on dokuzuncu yüzyıldaki âşık şiirleri incelenerek şiirlerdeki gelenek öğeleri sayesinde halk edebiyatındaki gelenek incelenmiş, ardından âşıkların birbirlerini nasıl etkiledikleri konusu üzerinde durulmuştur.Halk edebiyatının en önemli görevlerinden biri olan eğitim de bu yüzyıldaki eserlerde sıkça karşımıza çıkmaktadır. Halkın eğitiminde önemli bir yere sahip olan âşıkların şiirlerindeki eğitim unsurları hakkında da bu yüzyıldaki şiirlerden yola çıkarak örnekler verilmiştir.Çalışmanın son bölümünde ise on dokuzuncu yüzyıl bağlamında incelenen gelenek, etkileşim ve eğitim olgularının günümüz sosyal yaşama etkileri incelenmiştir. In this thesis, tradition, interaction and education concepts of folk poets in nineteenth century are covered. The folk poems and poets are examined as a resource of this work to come to a conclusion of effects of these concepts to today?s life.The situation of the nineteenth century is explained by working on the political aspects of the era. And then the effects of political factors on the social life of Anadolu are examined. After giving the information of nineteenth century?s political and social life, the folk literature is explained by detailing the most contributing folk poets and their poems. The tradition concept of folk poems is also examined and the overall folk literature tradition concept is explained by the help of nineteenth century?s tradition. The interaction between the folk poets are also examined and explained throughout the thesis.One of the most important missions of Turkish Folk Literature is ?education?. Education concept is obviously seen on the folk poems of nineteenth century. In this thesis, the education element in folk poems are examined and explained by the examples of the era?s folk poems.In the conclusion part of this work, the effects of tradition, education and interaction in nineteenth century poets on the social and political life of present are explained and discussed. 160

The applications of radio frequency identification (RFID) technology carry a tremendous potential for pharmaceutical industry. There is a pressing need to analyze the performance of RFID tags attached to various pharmaceutical dosage forms.The readability of RFID-tagged pharmaceutical products is, for the first time, systematically investigated by experiments. Factors considered include dosage forms, ion concentration in solution, angle of rotation, and distance between the RFID tag and the interrogator.Compared with empty container, the filling of any representative dosage forms causes deteriorated readability for the tag attached to container. Analysis of variance reveals that the effects of dosage forms, angle of rotation, and their interaction are statistically significant. In addition, an increase in distance (equivalent to higher RF attenuation level) and higher ion concentration in solution beyond a certain level have detrimental effect on tag readability.The analysis shows that the RFID tag readability is strongly dependent on the factors that are experimented with. The level of the factors for optimum RFID system performance should be adjusted based on the particular application.