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Millions of tons of “acetyls” such as acetic acid and acetic anhydride are produced each year. These basic building blocks of chemical industry are elaborated into esters, amides, and eventually polymer materials, pharmaceuticals, and other consumer products. The vast majority of acetyls are produced industrially using homogeneous catalysis, but exclusively using scarce and expensive precious metal catalysts (principally rhodium and iridium complexes). We report here that nickel catalysts supported by N-heterocyclic carbene ligands mediate the carbonylation of methyl esters, selectively producing anhydrides with high activity at low catalyst loading. Carbene supporting ligands with aryl substituents, which can be added as air-stable imidazolium salts, dramatically improve carbonylation performance relative to prior nickel catalysts supported by tertiary phosphine ligands, raising hopes for industrial application of base metal carbonylation catalysts.

In this paper, we leverage vehicle-to-vehicle (V2V) communication technology to implement computationally efficient decentralized algorithms for two-vehicle cooperative collision avoidance at intersections. Our algorithms employ formal control theoretic methods to guarantee a collision-free (safe) system, whereas overrides are only applied when necessary to prevent a crash. Model uncertainty and communication delays are explicitly accounted for by the model and by the state estimation algorithm. The main contribution of this work is to provide an experimental validation of our method on two instrumented vehicles engaged in an intersection collision avoidance scenario in a test track.

The corporate cash management problem has been addressed extensively in the literature. Actual implementations, however, are scarce. After discussion of the reasons for these limited implementation successes with practising cash managers, a Visual Interactive (VI) Modeling approach was proposed. This approach attempted to integrate concepts from past VI Modeling applications, Decision Support Systems (DSS), and 'soft systems' theory. Visual Interactive Models (VIMs) have been credited by Operational Researchers with a strong implementation focus, but a general methodology for building VIMs did not exist. This thesis formalized a development approach for VIMs and evaluated the results based on a practising cash manager's problem. The resulting problem formulation and solution algorithms differed from other cash management models in the literature, and the form of the VIM that resulted from this modeling approach differed from current applications. The results suggest that the proposed VIM building approach can derive an effective and implementable model. Further, this methodology offers support for complex problem situations including those where no physical picture of the system under study can be derived.