A Decentralized Control Framework for Energy-Optimal Goal Assignment and Trajectory Generation

This paper proposes a decentralized approach for solving the problem of moving a swarm of agents into a desired formation. We propose a decentralized assignment algorithm which prescribes goals to each agent using only local information. The assignment results are then used to generate energy-optimal trajectories for each agent which have guaranteed collision avoidance through safety constraints. We present the conditions for optimality and discuss the robustness of the solution. The efficacy of the proposed approach is validated through a numerical case study to characterize the framework's performance on a set of dynamic goals.Comment: 6 pages, 3 figures, to appear at the 2019 Conference on Decision and Control, Nice, F

Definiteness and determinacy

This paper distinguishes between definiteness and determinacy. Definiteness is seen as a morphological category which, in English, marks a (weak) uniqueness presupposition, while determinacy consists in denoting an individual. Definite descriptions are argued to be fundamentally predicative, presupposing uniqueness but not existence, and to acquire existential import through general type-shifting operations that apply not only to definites, but also indefinites and possessives. Through these shifts, argumental definite descriptions may become either determinate (and thus denote an individual) or indeterminate (functioning as an existential quantifier). The latter option is observed in examples like ‘Anna didn’t give the only invited talk at the conference’, which, on its indeterminate reading, implies that there is nothing in the extension of ‘only invited talk at the conference’. The paper also offers a resolution of the issue of whether possessives are inherently indefinite or definite, suggesting that, like indefinites, they do not mark definiteness lexically, but like definites, they typically yield determinate readings due to a general preference for the shifting operation that produces them.We thank Dag Haug, Reinhard Muskens, Luca Crnic, Cleo Condoravdi, Lucas Champollion, Stanley Peters, Roger Levy, Craige Roberts, Bert LeBruyn, Robin Cooper, Hans Kamp, Sebastian Lobner, Francois Recanati, Dan Giberman, Benjamin Schnieder, Rajka Smiljanic, Ede Zimmerman, as well as audiences at SALT 22 in Chicago, IATL 29 in Jerusalem, Going Heim in Connecticut, the Workshop on Bare Nominals and Non-Standard Definites in Utrecht, the University of Cambridge, the University of Gothenburg, the University of Konstanz, New York University, the University of Oxford, Rutgers University, the University of Southern California, Stanford University, and the University of Texas at Austin. Beaver was supported by NSF grants BCS-0952862 and BCS-1452663. Coppock was supported by Swedish Research Council project 2009-1569 and Riksbankens Jubileumsfond's Pro Futura Scientia program, administered through the Swedish Collegium for Advanced Study. (BCS-0952862 - NSF; BCS-1452663 - NSF; 2009-1569 - Swedish Research Council; Riksbankens Jubileumsfond's Pro Futura Scientia program

It's not what you expected! The surprising nature of cleft alternatives in French and English

While much prior literature on the meaning of clefts—such as the English form “it is X who Z-ed”—concentrates on the nature and status of the exhaustivity inference (“nobody/nothing other than X Z”), we report on experiments examining the role of the doxastic status of alternatives on the naturalness of c'est-clefts in French and it-clefts in English. Specifically, we study the hypothesis that clefts indicate a conflict with a doxastic commitment held by some discourse participant. Results from naturalness tasks suggest that clefts are improved by a property we term “contrariness” (along the lines of Zimmermann, 2008). This property has a gradient effect on felicity judgments: the more strongly interlocutors appear committed to an apparently false notion, the better it is to repudiate them with a cleft.Published versio

Beyond Reynolds: A Constraint-Driven Approach to Cluster Flocking

In this paper, we present an original set of flocking rules using an ecologically-inspired paradigm for control of multi-robot systems. We translate these rules into a constraint-driven optimal control problem where the agents minimize energy consumption subject to safety and task constraints. We prove several properties about the feasible space of the optimal control problem and show that velocity consensus is an optimal solution. We also motivate the inclusion of slack variables in constraint-driven problems when the global state is only partially observable by each agent. Finally, we analyze the case where the communication topology is fixed and connected, and prove that our proposed flocking rules achieve velocity consensus.Comment: 6 page

Clefts: Quite the contrary!

Much of the previous literature on English it-clefts – sentences of the form ‘It is X that Z’ – concentrates on the nature and status of the exhaustivity inference (‘nobody/nothing other than X Z’). This paper concerns the way in which it-clefts signal contrast. We argue that it-clefts signal a type of contrast that does not merely involve a salient antecedent, as on more traditional characterizations of contrast such as those of e.g. Kiss (1998) and Rooth (1992), but also involves a conflict between the speaker’s and the hearer’s beliefs, as under the characterization of contrast given by Zimmermann (2008, 2011), which we term contrariness. Results of a felicity judgment experiment suggest that clefts do have a preference for contrariness, and one which has a gradient effect on felicity judgments: the more strongly interlocutors appear committed to an apparently false notion, the better it is to repudiate them with a cleft.https://4f669968-a-62cb3a1a-s-sites.googlegroups.com/site/sinnundbedeutung21/proceedings-preprints/Destruel-Beaver-Coppock-SuB2016-FINAL.pdf?attachauth=ANoY7cpfzckWBy6psH6QCmbOCeXWS2nlL4bGgHHud2GpjKB1YQolksB00UtYzuvPRANOzWvWgfHdLZ7BP8zDYcT5wYIwr-1dBjw2g0-TC0Bic1ByVfjgj68pPdE9novwXm427ehkZI1E59JmiIvJnBKGxzYpI_AxMcKc-gEQuzu6DHXwJoLtzwm1FzFaHEX1LBq_yFSDgBzZajW2AHEFSiqmz1OVPTICm4zLB30AaHUxrtTBhWI1r0pmmX42IwVk9DtYfp0m6uvrsJLxJuvDhBPe-l3sJmHPcH2qhAtt6wqVMT7b-H6wX08=&attredirects=0Published versio

Experimental Validation of a Real-Time Optimal Controller for Coordination of CAVs in a Multi-Lane Roundabout

Roundabouts in conjunction with other traffic scenarios, e.g., intersections, merging roadways, speed reduction zones, can induce congestion in a transportation network due to driver responses to various disturbances. Research efforts have shown that smoothing traffic flow and eliminating stop-and-go driving can both improve fuel efficiency of the vehicles and the throughput of a roundabout. In this paper, we validate an optimal control framework developed earlier in a multi-lane roundabout scenario using the University of Delaware's scaled smart city (UDSSC). We first provide conditions where the solution is optimal. Then, we demonstrate the feasibility of the solution using experiments at UDSSC, and show that the optimal solution completely eliminates stop-and-go driving while preserving safety.Comment: 6 Pages, 4 Figures, 1 tabl

Smallholder Household Maize Production and Marketing Behavior in Zambia: Implications for Policy

CSO/MACO nationally-representative rural surveys provide important insights on smallholder crop marketing behavior from the 2001 and 2004 harvests. Only about 25 percent of smallholder farmers in Zambia sold maize in both seasons, and about 15-20 percent of smallholders sold fresh horticulture as well as groundnuts, with 11-13 percent selling cassava. From 6-10 percent of farmers produced and sold cotton. Overall, Zambian smallholder agriculture has become more diversified over the past decade, with maize, cassava, groundnuts, cotton, horticultural crops, and animal products all becoming important sources of cash revenue as well as production for home consumption (except, of course, cotton). Importantly in both seasons studied, horticulture crop sales are roughly equivalent to the value of maize sales nationwide There is substantial variation in farm income and off-farm income across small farm households, owing to disparities in landholding size, other productive assets, and variables affecting access to markets. Two percent of all smallholder farms nationwide accounted for over 40% of all the maize sold by smallholder households in Zambia in 2000/01 and 2003/04. This same two percent of smallholder households also accounted for about 17% and 20% of the total value of all crop sales of the smallholder sector. Poverty reduction policy options are severely constrained by these production and marketing patterns especially if operating though programs that raise market prices for sellers and buyers.food security, food policy, Zambia, maize, production, marketing, Crop Production/Industries, Q20,