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41.
With the proliferation of macroergonomic field research, it is time to carefully examine how such research should be managed and implemented. We argue that the importance of attending to high-quality implementation of field research is equal to that of methodological rigor. One way to systematically manage the implementation process is to adopt a change management framework, wherein the research project is conceptualized as an instance of organization-level change. Consequently, principles for successful organization-level change from the literature on change management can be used to guide successful field research implementation. This paper briefly reviews that literature, deriving 30 principles of successful change management, covering topics such as political awareness, assembling the change team, generating buy-in, and management support. For each principle, corresponding suggestions for macroergonomic field research practice are presented. We urge other researchers to further develop and adopt frameworks that guide the implementation of field research.  相似文献   
42.
Small unmanned aerial vehicles (UAV) are typically driven by Lithium polymer batteries. The batteries have their own dynamics, which changes during discharge. Classical approaches to altitude control assume a time-invariant system and therefore fail. Adaptive controllers require an identified system model which is often unavailable. Battery dynamics can be characterized and used for a battery model-based controller. This controller is useful in situations when no feedback from actuators (such as RPM or thrust) is available. After measuring the battery dynamics for two distinct types of batteries, a controller is designed and experimentally verified, showing a consistent performance during entire discharge test and a consequent flight verification.  相似文献   
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Journal of Materials Science - For transformers and inductors to meet the world’s growing demand for electrical power, more efficient soft magnetic materials with high saturation magnetic...  相似文献   
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46.
A systolic array for multi-dimensional fitting and interpolation using (nonlinear) radial basis functions is proposed. The fit may be constrained very simply to ensure that the resulting surface takes a pre-determined value at one or more specific points. The processor, which constitutes a form of nonlinear adaptive filter, behaves like a neural network based on the multi-layer, feed-forward perceptron model. One obvious application of such a network is as a pattern classifier, the constraints being used to ensure the correct classification of selected patterns.  相似文献   
47.
A split-flow thin (SPLITT) cell with a perpendicular driving force of one gravity has been utilized for the rapid separation of micron-sized particles from macromolecules. The procedure involves the simultaneous use of two transport mechanisms and thus two operating modes: a sedimentation process controls the displacement of the particles across the thickness of the thin channel, while diffusion controls the displacement of macromolecules. The theoretical equations for these two operating modes are summarized and it is shown how the two modes can be combined to yield specified recovery factors. The theory was tested on a mixture of 10 μm polystyrene latex beads and three different proteins. The observed separation was in excellent agreement with theory. Attempts to fractionate red blood cells and plasma proteins from whole blood were only partially successful as a consequence of the weak sedimentation of red blood cells. Various remedies to this problem are suggested, the most promising of which is the use of a SPLITT cell subject to mild centrifugal forces.  相似文献   
48.
Clinical characteristics of the primary tumor in 786 patients with superficial spreading melanoma were studied in a prospective sequential series of patients from the Melanoma Clinical Cooperative Group. The most useful features for early diagnosis were change in size and change in color, present in 71% and 55% respectively of patients with level II lesions. Increase in height of lesion correlated with more advanced disease. Ulceration and bleeding were predominantly found in advanced primary lesions and are consequently of limited use in early recognition. Awareness of the historical and clinical features of the primary tumor should result in early recognition and cure of most primary superficial spreading melanomas.  相似文献   
49.
Considerations for Microwave Remote Sensing of Ocean-Surface Salinity   总被引:4,自引:0,他引:4  
Parametric calculations of the microwave emission from the ocean surface are presented to determine the optimum electromagnetic wavelength for measuring salinity. At 800 MHz, a target accuracy of 240 parts per million is within the state of the art provided that emission due to surface roughness is negligible, or correctable, and that the error resulting from galactic radiation can be removed using an upward-looking antenna. Examples of salinity measurements relevant to physical oceanography are presented, and a possible spacecraft University of Massachusetts, Amherst, MA 01003.system is discussed.  相似文献   
50.
2 conferences, one in August 1955 and the other in August 1957, on "The Identification of Creative Scientific Talent" were supported financially by the National Science Foundation. Titles of research reports and authors are presented. Reports of special committees at each conference are summarized. "A multiplicity of hypotheses and problems needing research… emerged throughout both conferences. It is hoped that concurrent attacks on problems of creativity will be undertaken by researchers in industry, government, universities, and school systems." (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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