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More than half of the 170 million metric tons of polymers produced each year are polyolefins. Current technology uses highly active cationic catalysts, which suffer from an inability to tolerate heteroatoms such as oxygen, nitrogen, and sulfur. These systems require scrupulously clean starting materials and activating cocatalysts. A family of catalysts has been developed whose members are tolerant of both heteroatoms and less pure starting materials. These heteroatom-tolerant neutral late transition metal complexes are in fact highly active systems that produce high-molecular-weight polyethylene, polymerize functionalized olefins, and require no cocatalyst.

More than half of the 170 million metric tons of polymers produced each year are polyolefins. Current technology uses highly active cationic catalysts, which suffer from an inability to tolerate heteroatoms such as oxygen, nitrogen, and sulfur. These systems require scrupulously clean starting materials and activating cocatalysts. A family of catalysts has been developed whose members are tolerant of both heteroatoms and less pure starting materials. These heteroatom-tolerant neutral late transition metal complexes are in fact highly active systems that produce high-molecular-weight polyethylene, polymerize functionalized olefins, and require no cocatalyst.

This paper describes the requirements, data structures, and algorithms utilized in the run time Player Unit of the OneTESS program. OneTESS is a combined instrumentation suit designed to satisfy the requirements for both training and operational testing being developed by a team lead by AT&T. Specifically we will describe the terrain services and Player Unit services required for geometric pairing and engagement processing along with the accurate database design and procurement strategy required to build it. The paper will also describe a voxel based visualization engine adapted to perform dynamic terrain updates and high accurate test site preparation. We will also describe the process for procuring and testing the fidelity of the terrain environment and describe the analysis to answer the "what is good enough" question within the context of instrumentation accuracies and development strategies. Lastly we will discuss the implications and opportunities afforded by onboard environment models both for future test and training applications as well as in future deployable units.

Neutral salicylaldiminato Ni(II) complexes have been synthesized, and their structure has been confirmed by an X-ray analysis of complex 4e. These compounds are active catalysts for the polymerization of ethylene under mild conditions in the presence of a phosphine scavenger such as Ni(COD)_2 or B(C_6F_5)_3.

The ability to rapidly detect and identify potential targets both fixed and mobile from multiple sensor feeds is a critical function in network centric warfare. In this paper we describe the use of Image Differencing and 3D terrain database editing in order to fuse oblique aerial photos, IR sensor imagery, and other non-traditional data sources to produce battlefield metrics that support network centric operations. Such metrics include target detection, recognition, and location, and improved knowledge of the target environment. Key to our approach is the rapid generation of target and background signatures from high-resolution 1-meter object descriptor terrain databases. This technique utilizes the difference between measured and calculated sensor images to 1) update and correct knowledge of the terrain background, 2) register multi sensor imagery 3) identify potential/candidate targets based on residual image differencing and 3) measure and report target locations based on scene matching. The technique is especially suited for utilizing imagery from reconnaissance and remotely piloted vehicle sensors. It also holds promise for automation and real-time data reduction of battlefield sensor feeds and for improving now-time situational awareness. We will present the algorithms and approach utilized in the Image Differencing technique. We will also describe the software developed to implement the approach. Lastly we will present the results of experiments and benchmarks conducted to identify and measure target locations in test locations at Ft. Hood, TX and Ft. Hunter Liggett, CA.

The ability to rapidly and inexpensively generate terrain databases to replicate actual terrain is critical to insuring correlation between the results from live, virtual, and constructive simulations used in testing and evaluating weapons, sensors, and battlefield command and control systems. In this paper we describe a technique for producing battlefield terrain data sets from oblique aerial photos and other nontraditional data sources using image differencing and 3D terrain editing tools. This technique uses a feedback loop to calculate terrain data parameters from differences between actual sensor imagery and synthetic imagery of replicated terrain created by an image generator. The technique is especially well suited for updating knowledge of battlefield situations from reconnaissance and remotely piloted vehicle sensors. It also holds promise for automation and real-time data reduction of battlefield sensor feeds and improved now-time situational awareness. W e will present the algorithms and approach utilized in the Image Differencing technique. We will also describe the software developed to implement the approach. Lastly we will present the results of experiments and benchmarks conducted to measure the effectiveness and progress made toward real-time terrain database generation.

This thesis describes the preparation, characterization, and application of welldefined single-component group ten salicylaldimine complexes for the polymerization of ethylene to high molecular weight materials as well as the copolymerization of ethylene and functionalized olefins. After an initial introduction to the field, Chapter 2 describes the preparation of PPh3 complexes that contain a series of modified salicylaldimine and naphthaldimine ligands. Such complexes were activated for polymerization by the addition of cocatalysts such as Ni(COD)2 or B(C6F5)3. As the steric demand of the ligand set increased-the molecular weight, polymerization activity, and lifetime of the catalyst was observed to increase. In fact, complexes containing "bulky" ligands, such as the [Anthr,HSal] ligand (2.5), were found to be highly-active single component complexes for the polymerization of ethylene. Model hydrido compound were prepared-allowing for a better understanding of both the mechanism of polymerization and one mode of decomposition. Chapter 3 describes the effect which additives play on neutral NiII polymerization catalysts such as 2.5. The addition of excess ethers, esters, ketones, anhydrides, alcohols, and water do not deactivate the catalysts for polymerization. However, the addition of excess acid, thiols, and phosphines was observed to shut-down catalysis. Since excess phosphine was found to inhibit catalysis, "phosphine-free" complexes, such as the acetonittile complex (3.26), were prepared. The acetonitrile complex was found to be the most active neutral polymerization catalyst prepared to date. Chapter 4 outlines the use of catalyst 2.5 and 3.26 for the preparation of linear functionalized copolymers containing alcohols, esters, anhydrides, and ethers. Copolymers can be prepared with γ-functionalized-α-olefins, functionalized norbornenes, and functionalized tricyclononenes, with up to 30 mol% comonomer incorporation. Chapter 5 outlines the preparation of a series of PtII alkyl/olefin salicylaldimine complexes which serve as models for the active species in the NiII-catalyzed polymerization process. Understanding the nature of the M-olefin interaction as a the electronic and steric properties of the salicylaldimine ligand is varied has allowed for a number of predictions about the design of future polymerization systems.

A facile synthesis of nickel salicylaldimine complexes with labile dissociating ligands is described. In addition to producing highly active ethylene polymerization catalysts, important insights into the effect of ligand size on catalyst stability and information on the mechanism of polymerization are provided.