4,117 research outputs found
Numerical filtering for the operation of robotic manipulators through kinematically singular configurations
Includes bibliographical references (pages 551-552).Abstract also in Japanese.The loss of independent degrees of freedom at singular configurations is an inherent characteristic of robotic manipulators. Due to the unavoidable singularity of mechanical wrists, singular configurations cannot be avoided by simply restricting the bounds of the workspace. Techniques for operating at singular configurations without inducing unacceptably high joint velocities or end effector tracking errors are presented. Extensions to the damped least-squares formulation which incorporate estimates of the proximity to singularities and selective filtering of singular components are illustrated. The generality of the technique presented is illustrated in a computer simulation of a commercially available manipulator operating through singular configurations
A guide for many authors:Writing manuscripts in large collaborations
Writing manuscripts collaboratively affords both opportunities and challenges: Collaborative papers can benefit from the expertise, perspectives, and collective effort of the group but can lack coherence or be produced inefficiently. When collaborations are large, involving tens or hundreds of researchers, there are more and different opportunities and challenges, like appropriately crediting the contributions of many people. This paper is a practical guide for authors writing collaborative manuscripts, particularly those working in large collaborations. We emphasize the importance of deliberate leadership and describe five general strategies that lead authors can employ to maximize opportunities and navigate challenges: care in recruiting the author team, care in crediting the author team, clear and frequent communication, organized materials, and deliberate and early decision-making. For each, we offer specific tips in line with these strategies (e.g., use collaboration agreements, leverage Open Science practices). We then suggest how lead authors can structure the writing and revising process to produce a coherent manuscript and offer tips for submitting papers and responding to peer-reviews. A repository of resources for people writing manuscripts in collaborations is available at osf.io/dzwcn
The kinematics of the bi-lobal supernova remnant G 65.3+5.7 - Paper II
Further deep, narrow-band images in the light of [O III] 5007 A have been
added to the previous mosaic of the faint galactic supernova remnant G
65.3+5.7. Additionally longslit spatially resolved [O III] 5007 A line profiles
have been obtained at sample positions using the Manchester Echelle
Spectrometer at the San Pedro Martir observatory. The remnant is shown to be
predominantly bi-lobal with an EW axis for this structure. However, a faint
additional northern lobe has now been revealed.
Splitting of the profiles along the slit lengths, when extrapolated to the
remnant's centre, although uncertain suggests that the expansion velocity of
this remnant is between 124 and 187 km/s ie much lower than the 400 km/s
previously predicted for the forward shock velocity from the X-ray emission.
An expansion proper motion measurement of 2.1+-0.4 arcsec in 48 years for the
remnant's filamentary edge in the light of Halpha+[N II] has also been made.
When combined with an expansion velocity of ~155 km/s, a distance of ~800 pc to
G 65.3+5.7 is derived.
Several possibilities are considered for the large difference in the
expansion velocity measured here and the 400 km/s shock velocity required to
generate the X-ray emission. It is also suggested that the morphology of the
remnant may be created by a tilt in the galactic magnetic field in this
vicinity.Comment: 10 pages, 5 figures, accepted for publication in A&
Repressive Interactions Between Transcription Factors Separate Different Embryonic Ectodermal Domains.
The embryonic ectoderm is composed of four domains: neural plate, neural crest, pre-placodal region (PPR) and epidermis. Their formation is initiated during early gastrulation by dorsal-ventral and anterior-posterior gradients of signaling factors that first divide the embryonic ectoderm into neural and non-neural domains. Next, the neural crest and PPR domains arise, eithe
Prediction of protein function by discriminant analysis
Approximately 53% the protein sequences in the National Biomedical Research Foundation (NBRF) database can be allocated to one of 26 functional classes, each of which can be characterized by the joint occurrence of four or fewer attributes. The attributes reflect collective physicochemical properties of the sequences in a class, ranging from simple characteristics of composition, such as average hydrophobicity and net charge, to amphipathicity and the propensities of various residues to be in certain preferred configurations. In some, though not all instances, these variables can be related in a general way to topological or other structural features of the particular class they characterize. We show that the attributes permit 17 of the 26 groups to be filtered from all other proteins in the database with a misclassification error of less than 2%, and that the remaining 9 groups can be filtered with errors not exceeding 13%. Thus for a given functional class, the results point to the existence of relatively few characteristic variables which capture most of the intraclass similarity and interclass variability that is common and peculiar to members of that class.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26024/1/0000096.pd
EC03-101 Nebraska Seed Guide, 2004
This circular is a progress report of corn hybrid performance tests conducted by the Agronomy/Horticulture Department and the Northeast, South Central, West Central and Panhandle Research and Extension Centers of Nebraska and University of Wyoming at Torrington. Conduct of experiments and publication of results is a joint effort of the Agricultural Research Division and the Cooperative Extension Service
EC03-101 Nebraska Seed Guide, 2004
This circular is a progress report of corn hybrid performance tests conducted by the Agronomy/Horticulture Department and the Northeast, South Central, West Central and Panhandle Research and Extension Centers of Nebraska and University of Wyoming at Torrington. Conduct of experiments and publication of results is a joint effort of the Agricultural Research Division and the Cooperative Extension Service
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