3,560 research outputs found
Collision Resolutions in Cloth Simulation
We present a new collision resolution scheme for cloth collisions. Our main concern is to find dynamically convincing resolutions, i.e. positions and velocities of cloth elements, for any kinds of collisions occuring in cloth simulation (cloth-cloth, cloth-rigid, and cloth-cloth-rigid). We define our cloth surface as connected faces of mass particles where each particle is controlled by its internal energy functions. Our collision resolution method finds appropriate next positions and velocities of particles by conserving the particles’ momentums as accurately as possible. Cloth-cloth collision resolution is a special case of deformable N-body collision resolution. So to solve deformable N-body collision resolutions, we propose a new collision resolution method, which groups cloth particles into parts and resolves collisions between parts using the law of momentum conservation. To resolve collisions, we solve a system of linear equations derived from the collision relationships. A system of linear equations is built using a scheme adapted from the simultaneous resolution method for rigid N-body collisions [1]. For the special case where we can find cyclic relationships in collisions, we solve a system of linear inequalities derived from the collision relationships
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Presence of Meaning in Life Improves Response to Others’ Self-Promotion
Self-promotion is prevalent and aversive. We observe that people who think their life is meaningful tend to experience less negative emotional responses to others’ self-promotional attempts. A simple intervention involving a reflection on the presence of meaning in one’s life significantly improves recipients’ responses to others’ self-promotion
Electrical spin injection and detection in an InAs quantum well
We demonstrate fully electrical detection of spin injection in InAs quantum
wells. A spin polarized current is injected from a NiFe thin film to a
two-dimensional electron gas (2DEG) made of InAs based epitaxial multi-layers.
Injected spins accumulate and diffuse out in the 2DEG, and the spins are
electrically detected by a neighboring NiFe electrode. The observed spin
diffusion length is 1.8 um at 20 K. The injected spin polarization across the
NiFe/InAs interface is 1.9% at 20 K and remains at 1.4% even at room
temperature. Our experimental results will contribute significantly to the
realization of a practical spin field effect transistor
Regular projections of graphs with at most three double points
A generic immersion of a planar graph into the 2-space is said to be knotted
if there does not exist a trivial embedding of the graph into the 3-space
obtained by lifting the immersion with respect to the natural projection from
the 3-space to the 2-space. In this paper we show that if a generic immersion
of a planar graph is knotted then the number of double points of the immersion
is more than or equal to three. To prove this, we also show that an embedding
of a graph obtained from a generic immersion of the graph (does not need to be
planar) with at most three double points is totally free if it contains neither
a Hopf link nor a trefoil knot.Comment: 16 pages, 31 figure
Soft-mode turbulence in electrohydrodynamic convection of a homeotropically aligned nematic layer
The experimental study of electroconvection in a homeotropically aligned nematic ~MBBA! is reported. Thesystem undergoes a supercritical bifurcation ‘‘rest state-spatiotemporal chaos.’’ The chaos is caused by longwavelengthmodulation of the orientation of convective rolls. For the first time the observations both below andbeyond the Lifshitz point are accompanied by quantitative analysis of temporal autocorrelation functions ofturbulent modes. The dependence of the correlation time on the control parameter is obtained. A secondarybifurcation from normal to abnormal rolls is discussed
Dynamic Simulation for Zero-Gravity Activities
Working and training for space activities is difficult in terrestrial environments. We approach this crucial aspect of space human factors through 3D computer graphics dynamics simulation of crewmembers, their tasks, and physics-based movement modeling. Such virtual crewmembers may be used to design tasks and analyze their physical workload to maximize success and safety without expensive physical mockups or partially realistic neutral-buoyancy tanks. Among the software tools we have developed are methods for fully articulated 3D human models and dynamic simulation. We are developing a fast recursive dynamics algorithm for dynamically simulating articulated 3D human models, which comprises kinematic chains - serial, closed-loop, and tree-structure - as well as the inertial properties of the segments. Motion planning is done by first solving the inverse kinematic problem to generate possible trajectories, and then by solving the resulting nonlinear optimal control problem. For example, the minimization of the torques during a simulation under certain constraints is usually applied and has its origin in the biomechanics literature. Examples of space activities shown are zero-gravity self orientation and ladder traversal. Energy expenditure is computed for the traversal task
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Knockdown of Ant2 Reduces Adipocyte Hypoxia And Improves Insulin Resistance in Obesity.
Decreased adipose tissue oxygen tension and increased HIF-1α expression can trigger adipose tissue inflammation and dysfunction in obesity. Our current understanding of obesity-associated decreased adipose tissue oxygen tension is mainly focused on changes in oxygen supply and angiogenesis. Here, we demonstrate that increased adipocyte O2 demand, mediated by ANT2 activity, is the dominant cause of adipocyte hypoxia. Deletion of adipocyte Ant2 improves obesity-induced intracellular adipocyte hypoxia by decreasing obesity-induced adipocyte oxygen demand, without effects on mitochondrial number or mass, or oligomycin-sensitive respiration. This led to decreased adipose tissue HIF-1α expression and inflammation with improved glucose tolerance and insulin resistance in both a preventative or therapeutic setting. Our results suggest that ANT2 may be a target for the development of insulin sensitizing drugs and that ANT2 inhibition might have clinical utility
Coccoliths and Related Calcareous Nannofossils from the Upper Cretaceous Fencepost Limestone of Northwestern Kansas
17-22http://deepblue.lib.umich.edu/bitstream/2027.42/48470/2/ID320.pd
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Pleasure, Guilt and Regret in Hedonic Consumption: Revisiting the Vice-Virtue Categorization in Theories of Self-Control
The popular characterization of self-control conflicts as a choice between hedonic vices and utilitarian virtues leads to the unrealistic prediction that hedonic consumption is always accompanied by feelings of guilt and regret. The paradox is resolved by recognizing that excess consumption - rather than hedonics - is the defining characteristic of vices
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