Algorithms and architectures for robot vision

The scope of the current work is to develop practical sensing implementations for robots operating in complex, partially unstructured environments. A focus in this work is to develop object models and estimation techniques which are specific to requirements of robot locomotion, approach and avoidance, and grasp and manipulation. Such problems have to date received limited attention in either computer or human vision - in essence, asking not only how perception is in general modeled, but also what is the functional purpose of its underlying representations. As in the past, researchers are drawing on ideas from both the psychological and machine vision literature. Of particular interest is the development 3-D shape and motion estimates for complex objects when given only partial and uncertain information and when such information is incrementally accrued over time. Current studies consider the use of surface motion, contour, and texture information, with the longer range goal of developing a fused sensing strategy based on these sources and others

Global models: Robot sensing, control, and sensory-motor skills

Robotics research has begun to address the modeling and implementation of a wide variety of unstructured tasks. Examples include automated navigation, platform servicing, custom fabrication and repair, deployment and recovery, and science exploration. Such tasks are poorly described at onset; the workspace layout is partially unfamiliar, and the task control sequence is only qualitatively characterized. The robot must model the workspace, plan detailed physical actions from qualitative goals, and adapt its instantaneous control regimes to unpredicted events. Developing robust representations and computational approaches for these sensing, planning, and control functions is a major challenge. The underlying domain constraints are very general, and seem to offer little guidance for well-bounded approximation of object shape and motion, manipulation postures and trajectories, and the like. This generalized modeling problem is discussed, with an emphasis on the role of sensing. It is also discussed that unstructured tasks often have, in fact, a high degree of underlying physical symmetry, and such implicit knowledge should be drawn on to model task performance strategies in a methodological fashion. A group-theoretic decomposition of the workspace organization, task goals, and their admissible interactions are proposed. This group-mechanical approach to task representation helps to clarify the functional interplay of perception and control, in essence, describing what perception is specifically for, versus how it is generically modeled. One also gains insight how perception might logically evolve in response to needs of more complex motor skills. It is discussed why, of the many solutions that are often mathematically admissible to a given sensory motor-coordination problem, one may be preferred over others

On interactions of optimal climate policy and international trade. An assessment of border carbon measures.

Not only after the failure of the Copenhagen climate conference 2009, border carbon adjustment (BCA) has received growing attention in the climate policy debate as a measure to combat "carbon leakage" and force non-abating countries to tighter climate policies. In this paper, we study the strategic interactions between international trade and climate policy with a focus on the effectiveness of border measures. First, we analyze the main principles of unilateral climate policy with international trade in a small analytical model. Second, we examine welfare effects of WTO compatible carbon import tariffs in a stylized numerical integrated assessment model with explicit trade in commodities and analyze if BCA is a credible threat to force non-abating countries to implement stricter climate policies. We show that the terms of trade effects can, depending on trade patterns, ease or boost the prisoners dilemma of mitigating greenhouse gases. We further demonstrate that WTO conform BCA increases the effectiveness of climate policy and forces trading partners to reduce emissions. But as the results of the numerical model illustrate, welfare effects are depended on trade flows and are negative for realistic parameter values.International Trade; Environmental Policy; Border Tax Adjustment

Discussion of "Calibrated Bayes, for Statistics in General, and Missing Data in Particular" by R. J. A. Little

Discussion of "Calibrated Bayes, for Statistics in General, and Missing Data in Particular" by R. Little [arXiv:1108.1917]Comment: Published in at http://dx.doi.org/10.1214/10-STS318A the Statistical Science (http://www.imstat.org/sts/) by the Institute of Mathematical Statistics (http://www.imstat.org