94,999 research outputs found
Are you a researcher as well as a medical illustrator?
When we list the areas of practice for medical illustrators we always include research, but how involved in research are we? The aim of this activity is to encourage your professional development not just as a medical illustrator but your involvement with research whether that is undertaking your own research, undertaking evidence based practice (1) , working as part of a research team, advising researchers on the value of medical illustration or supporting a student undertaking a research project for their degree or post-graduate qualification
Stability of large horizontal-axis axisymmetric wind turbines
The stability of large horizontal axis, axi-symmetric, power producing wind turbines was examined. The analytical model used included the dynamic coupling of the rotor, tower and power generating system. The aerodynamic loading was derived from blade element theory. Each rotor blade was permitted tow principal elastic bending degrees of freedom, one degree of freedom in torsion and controlled pitch as a rigid body. The rotor hub was mounted in a rigid nacelle which may yaw freely or in a controlled manner. The tower can bend in two principal directions and may twist. Also, the rotor speed can vary and may induce perturbation reactions within the power generating equipment. Stability was determined by the eigenvalues of a set of linearized constant coefficient differential equations. All results presented are based on a 3 bladed, 300 ft. diameter, 2.5 megawatt wind turbine. Some of the parameters varied were; wind speed, rotor speed structural stiffness and damping, the effective stiffness and damping of the power generating system and the principal bending directions of the rotor blades. Unstable or weakly stable behavior can be caused by aerodynamic forces due to motion of the rotor blades and tower in the plane of rotation or by mechanical coupling between the rotor system and the tower
Automotive automation: Investigating the impact on drivers' mental workload
Recent advances in technology have meant that an increasing number of vehicle driving
tasks are becoming automated. Such automation poses new problems for the ergonomist.
Of particular concern in this paper are the twofold effects of automation on mental
workload - novel technologies could increase attentional demand and workload,
alternatively one could argue that fewer driving tasks will lead to the problem of reduced
attentional demand and driver underload. A brief review of previous research is
presented, followed by an overview of current research taking place in the Southampton
Driving Simulator. Early results suggest that automation does reduce workload, and that
underload is indeed a problem, with a significant proportion of drivers unable to
effectively reclaim control of the vehicle in an automation failure scenario. Ultimately,
this research and a subsequent program of studies will be interpreted within the
framework of a recently proposed theory of action, with a view to maximizing both
theoretical and applied benefits of this domain
Student Veterans/Service Members' Engagement in College and University Life and Education
Since the passage of the Post-9/11 Veterans Educational Assistance Act of 2008, also known as the Post-9/11 GI Bill, the enrollment of active-duty service members and veterans in American colleges and universities has increased substantially. According to the Department of Veterans Affairs, more than three-quarters of a million veterans have used their earned benefit to enroll in postsecondary courses. In response to the influx of veteran student enrollment, a group of higher education associations and veterans' organizations collaborated in 2009 and 2012 on a study that asked college and university administrators whether their institutions had geared up campus programs and services specifically designed to support the unique needs of veterans.1 The results indicated that administrators had indeed increased support levels, sometimes by quite significant margins.But how do student veterans/service members perceive their experiences at higher education institutions? To date, there is little or no information to assess whether the efforts by institutions to provide targeted programs and services are helpful to the veterans and service members enrolled in colleges and universities. Similarly, not much is known about the transition to postsecondary education from military service experienced by student veterans/service members, or whether these students are engaged in both academic programs and college and university life to their fullest potential. In this context, this issue brief explores student veteran/service member engagement in postsecondary education. The brief utilizes data from the 2012 National Survey of Student Engagement (NSSE), an annual survey of students enrolled in four-year universities, to assess how student veterans/service members perceive their integration on campus.A key finding is that student veterans/servicemembers are selective about the campus life and academic activities in which they invest their time. Student veterans/service members are morelikely to be first-generation students -- the first in their families to attend a college or university -- and older than nonveteran/civilian students; they therefore tend to have responsibilities outside of higher education that put constraints on their time.Student veterans/service members report placing greater emphasis on academic areas that they find essential for academic progress than on college and university life and activities -- academic or otherwise -- that are not essential for success in the courses in which they are enrolled. Student veterans/ service members are less likely to participate in co curricular activities, and they dedicate less time to relaxing and socializing than nonveteran/ civilian students
Increasing the Capacity of Primary Care Through Enabling Technology.
Primary care is the foundation of effective and high-quality health care. The role of primary care clinicians has expanded to encompass coordination of care across multiple providers and management of more patients with complex conditions. Enabling technology has the potential to expand the capacity for primary care clinicians to provide integrated, accessible care that channels expertise to the patient and brings specialty consultations into the primary care clinic. Furthermore, technology offers opportunities to engage patients in advancing their health through improved communication and enhanced self-management of chronic conditions. This paper describes enabling technologies in four domains (the body, the home, the community, and the primary care clinic) that can support the critical role primary care clinicians play in the health care system. It also identifies challenges to incorporating these technologies into primary care clinics, care processes, and workflow
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Serial persistence in individual real estate returns in the UK
Persistence of property returns is a topic of perennial interest to fund managers as it suggests that choosing those properties that will perform well in the future is as simple as looking at those that performed well in the past. Consequently, much effort has been expended to determine if such a rule exists in the real estate market. This paper extends earlier studies in US, Australian, and UK markets in two ways. First, this study applies the same methodology originally used in Young and Graff (1996) making the results directly comparable with those in the US and Australian property markets. Second, this study uses a much longer and larger database covering all commercial property data available from the Investment Property Databank (IPD), for the years 1981 to 2002 for as many as 216,758 individual property returns. While the performance results of this study mimic the US and Australian results of greater persistence in the extreme first and fourth quartiles, they also evidence persistence in the moderate second and third quartiles, a notable departure from previous studies. Likewise patterns across property type, location, time, and holding period are remarkably similar leading to the conjecture that behaviors in the practice of commercial real estate investment management are themselves deeply rooted and persistent and perhaps influenced for good or ill by agency effect
The ratio of molecular to atomic gas in spiral galaxies as a function of morphological type
In order to gain an understanding of the global processes which influence cloud and star formation in disk galaxies, it is necessary to determine the relative amounts of atomic, molecular, and ionized gas both as a function of position in galaxies and from galaxy to galaxy. With observations of the CO distributions in over 200 galaxies now completed as part of the Five College Radio Astronomy Observatory (FCRAO) Extragalactic CO Survey (Young et al. 1989), researchers are finally in a position to determine the type dependence of the molecular content of spiral galaxies, along with the ratio of molecular to atomic gas as a function of type. Do late type spirals really have more gas than early types when the molecular gas content is included. Researchers conclude that there is more than an order of magnitude decrease in the ratio of molecular to atomic gas mass as a function of morphological type from Sa-Sd; an average Sa galaxy has more molecular than atomic gas, and an average Sc has less. Therefore, the total interstellar gas mass to blue luminosity ratio, M sub gas/L sub B, increases by less than a factor of two as a function of type from Sa-Sd. The dominant effect found is that the phase of the gas in the cool interstellar medium (ISM) varies along the Hubble sequence. Researchers suggest that the more massive and centrally concentrated galaxies are able to achieve a molecular-dominated ISM through the collection of more gas in the potential. That gas may then form molecular clouds when a critical density is exceeded. The picture which these observations support is one in which the conversion of atomic gas to molecular gas is a global process which depends on large scale dynamics (cf Wyse 1986). Among interacting and merging systems, researchers find considerable scatter in the M(H2)/M(HI) ratio, with the mean ratio similar to that in the early type galaxies. The high global ratio of molecular to atomic gas could result from the removal of HI gas, the enhanced conversion of HI into H2, or both
Open and Closed Loop Stability of Hingeless Rotor Helicopter Air and Ground Resonance
The air and ground resonance instabilities of hingeless rotor helicopters are examined on a relatively broad parametric basis including the effects of blade tuning, virtual hinge locations, and blade hysteresis damping, as well as size and scale effects in the gross weight range from 5,000 to 48,000 pounds. A special case of a 72,000 pound helicopter air resonance instability is also included. The study shows that nominal to moderate and readily achieved levels of blade inertial hysteresis damping in conjunction with a variety of tuning and/or feedback conditions are highly effective in dealing with these instabilities. Tip weights and reductions in pre-coning angles are also shown to be effective means for improving the air resonance instability
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Comment on "Bayesian recursive parameter estimation for hydrologic models" by M. Thiemann, M. Trosset, H. Gupta, and S. Sorooshian
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