We investigate an idealized model for the size reduction and smoothing of a polygonal rock due to repeated chipping at corners. Each chip is sufficiently small so that only a single corner and a fraction of its two adjacent sides are cut from the object in a single chipping event. After many chips have been cut away, the resulting shape of the rock is generally anisotropic, with facet lengths a...

Three normal volunteers, 58 normal patients, and three patients with parotid tumors were studied with a 0.3 T permanent-magnet imaging system to directly image the intraparotid facial nerve. On T1-weighted images the nerve appeared as a curvilinear structure of relatively low signal intensity within the fatty, high-signal parotid parenchyma. Its major divisions and branches could be imaged only...

BACKGROUND AND PURPOSE The number of centers currently performing 3D fat-suppressed isotropic imaging is limited. If the angular orientations of the major lumbosacral plexus nerves on 3D isotropic MR neurography could be determined, similar planes could be prescribed during acquisition of 2D or 3D nonisotropic techniques for optimal depiction of various nerves. Our aim was to determine oblique ...

In the successful branch-and-cut approach to combinatorial optimization, linear inequalities are used as cutting planes within a branch-and-bound framework. Although researchers often prefer to use facet-inducing inequalities as cutting planes, good computational results have recently been obtained using disjunctive cuts, which are not guaranteed to be facet-inducing in general. A partial expla...

The human opposable thumb enables the hand to perform dexterous manipulation of objects, which requires well-coordinated digit force vectors. This study investigated the directional coordination of force vectors generated by the thumb and index finger during precision pinch. Fourteen right-handed, healthy subjects were instructed to exert pinch force on an externally stabilized apparatus with t...

The title compound, C(7)H(9)N(3)S(2), crystallizes with two unique mol-ecules in the unit cell, both present as thio-semicarbazide tautomers. The mol-ecules differ principally in the dihedral angles between the thio-phene ring planes and the planes through the non-H atoms of the hydrazinecarbothio-amide units, viz. 9.80 (8)° for one mol-ecule and 19.37 (7)° for the other. The hydrazinecarbothio...

purpose: controversy has recently risen about the presence of compensatory ocular countertorsion (coct) after head tilt. this study was performed to define the functional range of this phenomenon. methods: cycloplegic autorefraction was performed on 80 eyes with regular astigmatism 2d. objective autorefraction was performed in normal position, right and left head tilt positions of 5º, 10º, 15º,...

We present a new branch-and-cut algorithm for the capacitated vehicle routing problem (CVRP). The algorithm uses a variety of cutting planes, including capacity, framed capacity, generalized capacity, strengthened comb, multistar, partial multistar, extended hypotour inequalities, and classical Gomory mixed-integer cuts. For each of these classes of inequalities we describe our separation algor...

One fails to recognize an unfamiliar object across changes in viewing angle when it must be discriminated from similar distractor objects. View-invariant recognition gradually develops as the viewer repeatedly sees the objects in rotation. It is assumed that different views of each object are associated with one another while their successive appearance is experienced in rotation. However, natu...