Nonlinear internal models for output regulation

In this paper we show how nonlinear internal models can be effectively used in the design of output regulators for nonlinear systems. This result provides a significant enhancement of the non-equilibrium theory for output regulation, which we have presented in the recent paper entitled "Limit Sets, Zero Dynamics, and Internal Models in the Problem of Nonlinear Output Regulation"

Communication: Essential Element at International Centers

The first international agricultural research center began operations less than 20 years ago. Not even the most optimistic and enthusiastic supporter of the International Rice Research Institute (IRRI), the first center, would have dared to dream, let alone predict, either its dramatic success or the consequences for peoples and other commodities around the world

Is this Belt One Size Fits All? China\u27s Belt and Road Initiative

Widely considered one of the largest and most ambitious infrastructure projects in human history, China’s Belt and Road Initiative [BRI] has made major headway since its inception in 2013. Although the BRI is formally adopted under the Chinese Communist Party Constitution as an initiative to secure “shared growth through discussion and collaboration,” the BRI is much more than these words convey. This Comment briefly introduces an overview of the BRI, including its components and early research on its effects on participating countries and regions. The Comment then conducts an in-depth analysis of four countries who have participated in the BRI with varying degrees of success. Next, the Comment discusses various international concerns surrounding the BRI, including possible debt diplomacy and military motivations. Finally, the Comment concludes that although the BRI should be applauded for its bold aspirations and developments, it should also be closely monitored by the international community to mitigate any deleterious effects incurred by BRI participants

What\u27s Happening on the International Scene?

Twenty-eight years ago, AAACE was meeting at Mo Ranch in the wilds of Texas

Dilemmas of the Communication Consultant Abroad

When first invited to talk here, I suggested the title: Mom, are them green things oranges? While neither professional nor academic, the title rather vividly describes the Dilemmas of the Communication Consultant Abroad

Small-scale movement and migration cues of Australian bass (Percalates novemaculeata) in an urbanised river

Urban river catchments are often severely affected by human activities but may still retain significant biodiversity. Surprisingly little is known about the behaviour of urban fishes, even those popular with anglers. Key environmental variables that trigger fish behaviour, such as river flow, are highly affected by instream structures including weirs and changes in the natural flow regime. Here, we used acoustic telemetry to examine the movements of Australian bass in a river located in suburban Sydney, Australia. We found that fish tended to be nocturnally active, however, small-scale movements were highly idiosyncratic and less associated with river flow than other factors. Larger-scale movements associated with spawning migrations were strongly correlated with winter floods. Half of the tagged fish migrated to the confluence of the river with Sydney Harbour to breed. Their return migration was hampered by a weir, but the provision of a new fish way facilitated successful return to freshwater at high tide. Despite occupying a highly affected, urban catchment fish behaviour showed similarity to those occupying more natural drainages. Our results highlight the importance of maintaining natural river flows in urban catchments and sustaining fish movement and migration capabilities through the installation of appropriate fish passage devices

Inhomogeneous non-Gaussianity

We propose a method to probe higher-order correlators of the primordial density field through the inhomogeneity of local non-Gaussian parameters, such as f_NL, measured within smaller patches of the sky. Correlators between n-point functions measured in one patch of the sky and k-point functions measured in another patch depend upon the (n+k)-point functions over the entire sky. The inhomogeneity of non-Gaussian parameters may be a feasible way to detect or constrain higher-order correlators in local models of non-Gaussianity, as well as to distinguish between single and multiple-source scenarios for generating the primordial density perturbation, and more generally to probe the details of inflationary physics.Comment: 16 pages, 2 figures; v2: Minor changes and references added. Matches the published versio

Space Trajectory Error Analysis Program (STEAP) for halo orbit missions. Volume 2: Programmer's manual

The six month effort was responsible for the development, test, conversion, and documentation of computer software for the mission analysis of missions to halo orbits about libration points in the earth-sun system. The software consisting of two programs called NOMNAL and ERRAN is part of the Space Trajectories Error Analysis Programs. The program NOMNAL targets a transfer trajectory from earth on a given launch date to a specified halo orbit on a required arrival date. Either impulsive or finite thrust insertion maneuvers into halo orbit are permitted by the program. The transfer trajectory is consistent with a realistic launch profile input by the user. The second program ERRAN conducts error analyses of the targeted transfer trajectory. Measurements including range, doppler, star-planet angles, and apparent planet diameter are processed in a Kalman-Schmidt filter to determine the trajectory knowledge uncertainty