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This article presents a validation study of the popular aeroservoelastic code suite OpenFAST leveraging weeks of measurements obtained during normal operation of a 2.8 MW land-based wind turbine. Measured wind conditions were used to generate one-to-one turbulent flow fields (i.e., comparing simulation to measurement in 10 min increments, or bins) through unconstrained and constrained assimilation methods using the kinematic turbulence generators TurbSim and PyConTurb. A total of 253 bins of 10 min of normal turbine operation were selected for analysis, and a statistical comparison in terms of performance and loads is presented. We show that successful validation of the model was not strongly dependent on the type of inflow assimilation method used for mean quantities of interest, which had median modeling errors per wind-speed interval generally within 5 %–10 % of the measurement. The type of inflow assimilation method did have a larger effect on the fatigue predictions for blade-root flapwise and tower-base fore–aft quantities, which surprisingly saw larger errors from the assumed higher-fidelity assimilation methods. Avenues for further work are discussed and include possible improvements to the aerodynamic, structural, and controller modeling that may offer insight on the origin of the up to ∼ 40 % median overprediction of fatigue for these quantities. [ABSTRACT FROM AUTHOR]

Wind loading is a primary contributor to structural design costs of concentrating solar-thermal power collectors, such as heliostats and parabolic troughs. These structures must resist the mechanical forces generated by turbulent wind, while the reflector surfaces must maintain optimal optical performance. Studying wind-driven loads at a full-scale, operational concentrating solar-thermal power plant provides insights into the wind impact on the solar collector field beyond the capabilities of wind tunnel tests or state-of-the-art simulations. We conducted comprehensive field measurements of the atmospheric turbulent wind conditions and the resulting structural wind loads on parabolic troughs at the Nevada Solar One plant over a two-year period. The measurement setup included meteorological masts and structural load sensors on four trough rows. Additionally, a lidar scanned the horizontal plane above the trough field. In this study, we describe the high-resolution dataset characterizing the complex flow field and resulting structural loads. This first-of-its-kind dataset will enhance the understanding of wind loading on collector structures and will help in designing the next-generation solar collectors and photovoltaic trackers. [ABSTRACT FROM AUTHOR]

Should the writing construct be assessed through handwriting or keyboarding? As the only major language entirely without a syllabary or alphabet, the Chinese writing system is unique among modern languages, thus the question of writing proficiency is complicated by character recall. Most of the testing research comparing text entry methods has been conducted in English and has found that keyboarding and handwriting can be used interchangeably. This paper reports the outcome of a study comparing the results of handwritten and typed versions of the Chinese ACTFL Writing Proficiency Test (WPT). L2 Chinese students (n = 25) with Intermediate to Superior speaking skills were randomly divided into two groups and took both WPT versions in a counterbalanced design. Keyboarding resulted in significantly higher test scores [repeated measures ANOVA F(1, 23) = 62.7, p <.001, effect size partial eta squared =.73]. Keyboarding was on average 1.69 ACTFL sublevels higher than handwriting. Finally, this paper will discuss the writing construct in Chinese along with pedagogical implications around curricular decisions on teaching and assessing handwriting vs. keyboarding. [ABSTRACT FROM AUTHOR]

This paper is a socio-linguistic report of Veun Sai, a small Cambodian village in the Northeastern province of Ratanakiri near the border of Laos and Vietnam. The village is located in a multi-lingual context where Hakka Chinese, Khmer, and Laotian are spoken side-by-side and each language has a distinct role. Hence, the Veun Sai Chinese village is in fact a multi-cultural village bound together by a Chinese thread. This paper provides background on Chinese communities Cambodia historically and considers issues of identity relevant to Sino-Cambodians generally. The report is based on short interviews with 20 residents. [ABSTRACT FROM AUTHOR]

Should the writing construct be assessed through handwriting or keyboarding? As the only major language entirely without a syllabary or alphabet, the Chinese writing system is unique among modern languages, thus the question of writing proficiency is complicated by character recall. Most of the testing research comparing text entry methods has been conducted in English and has found that keyboarding and handwriting can be used interchangeably. This paper reports the outcome of a study comparing the results of handwritten and typed versions of the Chinese ACTFL Writing Proficiency Test (WPT). L2 Chinese students (n = 25) with Intermediate to Superior speaking skills were randomly divided into two groups and took both WPT versions in a counterbalanced design. Keyboarding resulted in significantly higher test scores [repeated measures ANOVA F(1, 23) = 62.7, p <.001, effect size partial eta squared =.73]. Keyboarding was on average 1.69 ACTFL sublevels higher than handwriting. Finally, this paper will discuss the writing construct in Chinese along with pedagogical implications around curricular decisions on teaching and assessing handwriting vs. keyboarding. [ABSTRACT FROM AUTHOR]

In this work, we extend the AeroDyn module of OpenFAST to support arbitrary collections of wings, rotors, and towers. The new standalone AeroDyn driver supports arbitrary motions of the lifting surfaces and complex turbulent inflows. Aerodynamics and inflow are assembled into one module that can be readily coupled with an elastic solver. We describe the features and updates necessary for the implementation of the new AeroDyn driver. We present different case studies of the driver to illustrate its application to concepts such as multirotors, kites, or vertical-axis wind turbines. We perform verification and validation of some of the new features using the following test cases: elliptical wings, horizontal-axis wind turbines, and 2D and 3D vertical-axis wind turbines. The wind turbine simulations are compared to existing tools and field measurements. We use this opportunity to describe some limitations of current models and to highlight areas that we think should be the focus of future research in wind turbine aerodynamics. [ABSTRACT FROM AUTHOR]

Small‐scale wind turbines have market opportunities in distributed energy generation applications but face future challenges in remaining cost competitive compared with solar photovoltaic systems. High unit costs can be attributed to design conservatism when calculating fatigue loads of key structural components such as the blades. In this study, we use the aeroelastic software FAST to highlight limitations of the International Electrotechnical Commission 61400‐2:2013 small wind turbine design standard for calculating fatigue life using the simplified load model. We present a modified method for calculating the fatigue spectra of small wind turbine blades. An advantage of this method is that it does not require complex aeroelastic simulations or field measurements. This modified method is intended to be implemented early in the blade design stage, such as during rotor optimization simulations, allowing for multiple rotor configurations to be rapidly compared. [ABSTRACT FROM AUTHOR]

The objective of this paper is to compare field data from a scanning lidar mounted on a turbine to control-oriented wind turbine wake models. The measurements were taken from the turbine nacelle looking downstream at the turbine wake. This field campaign was used to validate control-oriented tools used for wind plant control and optimization. The National Wind Technology Center in Golden, CO, conducted a demonstration of wake steering on a utility-scale turbine. In this campaign, the turbine was operated at various yaw misalignment set points, while a lidar mounted on the nacelle scanned five downstream distances. Primarily, this paper examines measurements taken at 2.35 diameters downstream of the turbine. The lidar measurements were combined with turbine data and measurements of the inflow made by a highly instrumented meteorological mast on-site. This paper presents a quantitative analysis of the lidar data compared to the control-oriented wake models used under different atmospheric conditions and turbine operation. These results show that good agreement is obtained between the lidar data and the models under these different conditions. [ABSTRACT FROM AUTHOR]

Renewed interest in yaw control for wind turbine and power plants for wake redirection and load mitigation demands a clear understanding of the effects of running with skewed inflow. In this paper, we investigate the physics of yawed operations, building up the complexity from a simplified analytical treatment to more complex aeroelastic simulations. Results in terms of damage equivalent loads (DELs) and extreme loads under misaligned conditions of operation are compared to data collected from an instrumented, utility-scale wind turbine. The analysis shows that multiple factors are responsible for the DELs of the various components and that airfoil aerodynamics, elastic characteristics of the rotor, and turbulence intensities are the primary drivers. Both fatigue and extreme loads are observed to have relatively complex trends with yaw offsets, which can change depending on the wind-speed regime. Good agreement is found between predicted and measured trends for both fatigue and ultimate loads. [ABSTRACT FROM AUTHOR]

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Recent public policy has sought to broaden the role of Medicaid, which typically serves people with limited income, to include increasing employment among people with disabilities and supporting people with disabilities who are working. In late 2001, we surveyed Medicaid agencies regarding their provision of services to working people with disabilities and collaboration with disability- and employment-related agencies and services. One third to one half of respondents were involved in Workforce Investment Act implementation at the state level and/or were implementing a Medicaid Buy-In option for working adults with disabilities. Collaboration with disability- or employment-focused agencies occurred at similarly moderate rates, with activities such as trainings and working groups being the most common types of collaboration reported. These findings suggest that while policy efforts to expand Medicaid's role in supporting employment of people with disabilities have been somewhat successful, there is potential for considerably more engagement of Medicaid agencies in this important issue. [ABSTRACT FROM AUTHOR]

The intent of this paper is the comparison of data from the state Vocational Rehabilitation (VR) system to data from studies within the general population of three measures related to participation in postsecondary education (PSED) of persons with disabilities. The three measures compared include the following: (1) the VR system's incidence of enrollment for people with disabilities and the incidence reported by other studies; (2) the rate of participation in postsecondary education for people with disabilities versus the rate for the general population; and (3) the employment-related outcomes of people with disabilities compared to outcomes for the general population and across disability groups. [ABSTRACT FROM AUTHOR]

Title IX has encouraged school administrators to work toward gender equity in athletics spending, and now many more women participate in college sports and earn college athletics scholarships than in the time before Title IX. This study was designed to assess whether Title IX has translated into equal coverage of men's and women's athletics by campus media. Based on these exploratory findings, the answer is no. College newspapers in the study covered male athletes and events in 72.7% of their sports stories, and college television operations devoted 81.5% of their sports stories to males. The overall amount of time or space devoted to comments from female or male participants or observers mirrored the discrepancy in the number of stories devoted to male versus female athletes. However, when college sports media did cover female athletes, the quality of the coverage was equivalent to that given to men. There was no significant difference in the average number of words per print story or the average number of seconds per broadcast story, nor was there a difference in the way the stories were presented based on the sex of the athletes. However, the huge disparity in the quantity of coverage indicates that campus media mirror professional media in regard to gender equity in their coverage of sports. [ABSTRACT FROM AUTHOR]

This study examines the amount of NBC's 2000 Olympics coverage devoted to women's athletics. Analysis showed that women received proportionately less coverage in 2000 than they did in 1996 on the U.S. network, and that coverage focused on individual events, with women competing in team sports receiving relatively little coverage. As was the case in 1996, women who competed in 2000 in sports involving power or hard physical contact received almost no attention. [ABSTRACT FROM AUTHOR]

This article presents the results of a secondary analysis of the RSA-911 database from the Rehabilitation Services Administration. All successful vocational rehabilitation (VR) closures for individuals with mental retardation, cerebral palsy, and epilepsy for five data points between 1985 and 1995 were investigated. Trends in the use of competitive employment versus sheltered workshops and employment outcomes (hours and earnings) are examined. The use of supported employment in the VR system and its outcomes are also discussed. An additional analysis of the impact of the 1992 Rehabilitation Act amendments is included. Findings include increased incidence of competitive employment and supported employment services but a decrease in real earnings. [ABSTRACT FROM AUTHOR]

Presents an annotated bibliography concerning topics related to urban community colleges. 'Making Connections,' by J. Fitzgerald and D. Jenkins; 'Building College and Community Services for Single Parents and Displaced Homemakers Project.'