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191.
This paper presents a disturbance rejection scheme for walking robots under unknown external forces and moments. The disturbance rejection strategy, which combines the inverse dynamics control with the acceleration projection onto the ZMP (zero moment point)-plane, can ensure the overall dynamic stability of the robot during tracking the pre-computed trajectories. Under normal conditions, i.e., the system is dynamically balanced, a primary inverse dynamics control is utilized. In the case that the system becomes unbalanced due to external disturbances, the acceleration projection control (APC) loop, will be activated to keep the dynamic stability of the walking robot through modifying the input torques. The preliminary experimental results on a robot leg demonstrate that the proposed method can actually make the robot keep a stable motion under unknown external perturbations. 相似文献
192.
Johannes S. Binder Michael Scholz Stephan Ellmann Michael Uder Robert Grützmann Georg F. Weber Christian Krautz 《Anatomical sciences education》2021,14(1):22-31
Integration of medical imaging into preclinical anatomy courses is already underway in many medical schools. However, interpretation of two-dimensional grayscale images is difficult and conventional volume rendering techniques provide only images of limited quality. In this regard, a more photorealistic visualization provided by Cinematic Rendering (CR) may be more suitable for anatomical education. A randomized, two-period crossover study was conducted from July to December 2018, at the University Hospital of Erlangen, Germany to compare CR and conventional computed tomography (CT) imaging for speed and comprehension of anatomy. Sixteen students were randomized into two assessment sequences. During each assessment period, participants had to answer 15 anatomy-related questions that were divided into three categories: parenchymal, musculoskeletal, and vascular anatomy. After a washout period of 14 days, assessments were crossed over to the respective second reconstruction technique. The mean interperiod differences for the time to answer differed significantly between the CR–CT sequence (−204.21 ± 156.0 seconds) and the CT–CR sequence (243.33 ± 113.83 seconds; P < 0.001). Overall time reduction by CR was 65.56%. Cinematic Rendering visualization of musculoskeletal and vascular anatomy was higher rated compared to CT visualization (P < 0.001 and P = 0.003), whereas CT visualization of parenchymal anatomy received a higher scoring than CR visualization (P < 0.001). No carryover effects were observed. A questionnaire revealed that students consider CR to be beneficial for medical education. These results suggest that CR has a potential to enhance knowledge acquisition and transfer from medical imaging data in medical education. 相似文献
193.
AbstractPublic Management and Public Administration are important professions for an emerging democracy such as South Africa. They operate as the interface between state and public and are responsible for enacting many of the government's policies and social initiatives. Concerns about a lack of capacity in the sector suggest that those in these roles may be unable to meet the demands of the workplace. This article reports on a study that responded to calls for the curriculum to address such concerns by interrogating the knowledge structures of Public Management and Public Administration programmes in higher education. Interviews, textbooks and course guides were analysed to illuminate the forms of knowledge being legitimated in curricula. The study found that the focus on knowledge, skills and processes might be at the expense of a focus on the development of particular attributes or dispositions in the knowers. Furthermore, the knowledge level focus was limited in that it was highly contextualised and “light” on theory, raising questions about the acquisition of powerful knowledge needed for good governance and critical engagement in the public sector. The study recommends that both programmes include more conceptual knowledge; exposure to critical powerful forms of knowledge; and the development of particular attributes and dispositions. 相似文献
194.
Schürmann Linda Gaschler Robert Quaiser-Pohl Claudia 《European Journal of Psychology of Education - EJPE》2021,36(3):739-757
European Journal of Psychology of Education - Preservice teachers should learn about motivation theory during their university studies in order to be able to motivate their students in their future... 相似文献
195.
196.
This paper treats the problem of transmitting a Gaussian discrete-time Markov process over a time-discrete additive white Gaussian channel with noiseless feedback which is subjected to statistically unknown jamming noise (satisfying a given power constraint). The channel is used more than once during the interval between the production of successive source letters, and the jamming noise is either allowed to be correlated with the encoder output, or forced to be totally independent of it. The complete solution obtained in the paper under a minimax criterion indicates that the optimum encoder-decoder structures are linear,and the least favorable jamming noise is a Gaussian process. 相似文献
197.
Knowledge Management Research & Practice - 相似文献
198.
ZHOU Shanjü;YANG Ying(Department of Admissions and Under-Graduate Guidance,Zunyi Normal University,Zunyi,Guizhou,563000,China;No.3 Middle School of Zhijin County,Zunyi,Guizhou,552100, China) 相似文献
199.
200.
The Relative Efficiency of Departments at a Turkish Engineering College: A Data Envelopment Analysis
In this study, Data Envelopment Analysis is used to measure relative efficiencies of academic departments of an engineering
college. Input and output criteria are determined and measured utilizing the academic personnel performance measurement scheme
of the College. New measures are developed to compare departments of different disciplines. The discriminating power of the
measurement models is improved by restricting criteria weights directly and by using a multiple criteria decision making approach.
Sensitivity of the results to exclusion of a criterion and changes in relative importance of the criteria is analyzed. Evaluation
of the results jointly by the college administration and the departments is explained for a successful efficiency improvement
mechanism. 相似文献