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The military concept of a Center of Gravity (COG) in conflicts, introduced by Carl von Clausewitz in the 1820s, is now an element of numerous military doctrines that planners draw on in designing strategies for winning wars. Over the last twenty-five years, the concept has become increasingly central to U.S. warfare doctrine. The world has changed a great deal since the introduction of COG. And in today's asymmetric environment, in which non-state actors use unconventional tactics, it is becoming extremely difficult to apply the COG concept. The primary reason for this difficulty is that non-state actors do not operate as a unitary body, which makes it difficult to target a COG that would lead to a decisive victory. The purpose of this thesis is to analyze both conflicts in which state-sanctioned militaries' applied the COG concept and conflicts in which non-state actors used asymmetric tactics. The thesis attempts to determine the applicability of COG in an asymmetric environment. If the Center of Gravity concept is determined inapplicable, then the U.S. military must either redefine it or create a new means to deal with this new type or warfare. / US Navy (USN) author.

This thesis focuses on developing and analyzing a model for an aerially deployed real-time targeting sensor net to close the current gap that exists between the potential technological-doctrinal capability within society and that of the military. It outlines current real-time targeting need due to the decomposition of warfare after the fall of the Soviet Union, and portrays the targeting discrepancies in the Global War on Terror. From end-user surveys requirements are layed out for a system of systems to meet targeting needs. A feasible solution consisting of a system architecture anchored in existing commercial off the shelf technology is proposed to meet the discrete deliverables necessary to accomplish targeting goals to deal with asymmetric threats in opaque environments. / US Navy (USN) author.

Thesis advisor: James Morken / Asymmetric hydroformylation (AHF) is a metal-catalyzed reaction in which CO and H2 are added across an olefin to form a new carbon-carbon bond. AHF has perfect atom-economy and is an ideal way to form a chiral aldehyde. However, the utility of branch selective hydroformylation is limited due to a lack of readily available ligands and restrictions on a wide variety of terminal olefins. Herein, Rh-catalyzed asymmetric hydroformylation of 1-alkenes is reported using commercially available Ph-BPE ligand to generate α-chiral aldehydes. A wide range of terminal olefins were explored and all showed high enantioselectivity (up to 98:2 er) and good regioselectivity (up to 15:1 branched to linear ratio). / Thesis (MS) — Boston College, 2015. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Tian Yuan. / "September 2000." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (p. 114-136). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Thesis (Ph. D.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains viii, 161, [213] p. : ill. Includes abstract. Includes bibliographical references (p. 154-161).

In order to extend the scope of asymmetric conjugate alkenylation catalyzed by 3,3′-disubstituted binaphthols, two classes of compounds were examined. Asymmetric 1,4-addition of alkenylboronates onto N-acylimines was investigated. Chiral allylic amides were obtained in good yields and high enantioselectivities. This represents one of the very few methods for synthesizing chiral allylic amides without the use of transition metal catalysts. Chiral binaphthol-catalyzed conjugate addition of alkenylboronates to -silyl--unsaturated ketones afforded highly enantioenriched chiral -silylcarbonyls. Asymmetric addition onto -silyl-enones is still a largely unexplored area, with only a handful of transition metal-catalyzed reactions reported. The first asymmetric reaction using these silicon-containing enones without using transition metal were described.

Power amplifiers are an indispensible part of the wireless communication systems. Conventional PAs provide peak efficiency at peak output power which is obtained at a certain fixed optimum resistance. These kind of amplifiers are normally called switched-mode power amplifiers (SMPAs) and are used for constant envelope signals. However, there is low efficiency at low output power which is the linear operation of a PA and is used for the amplification of non-constant envelope signals. For an optimum PA design, linearity and efficiency are the requirements. There are efficiency  enhancement techniques and Doherty architecture is one such approach. Classical Doherty (symmetric) approach entertains the signals that have peak to average power ratio (PAPR) of 6 dB. Applications like Long Term Evolution (LTE) having high PAPR of nearly 9 dB demand efficiency throughout the back-off range. Therefore the challenge is to design and implement an asymmetric Doherty power amplifier that ensures high efficiency in the back-off range greater than 6 dB. This work presents the design and implementation of an Asymmetric Doherty Power Amplifier (ADPA) for 12 dB back-off at 2.65 GHz in Gallium Nitride (GaN) High Electron Mobility Transistors (HEMTs) technology. The carrier and peaking amplifiers are biased in class-B and C mode of operations, respectively. A branchline coupler is used to divide the input signal equally to amplifiers input. A 10 W GaN HEMT transistor is used as an active device for both amplifiers. The design has been implemented with ideal transmission lines and then shifted to microstrip lines using 508 um substrate. The measurement results of the ADPA prototype, when drain of carrier and peaking devices are biased at 24 V and 28 V  respectively, showed an input power back of (IPBO) of 9.68 dB with almost same power added efficiency (PAE) of 44% throughout the entire back-off range. The simulations are done with Agilent ADS and Momentum is used for Electromagnetic (EM) simulation.

In order to extend the scope of asymmetric conjugate alkenylation catalyzed by 3,3′-disubstituted binaphthols, two classes of compounds were examined. Asymmetric 1,4-addition of alkenylboronates onto N-acylimines was investigated. Chiral allylic amides were obtained in good yields and high enantioselectivities. This represents one of the very few methods for synthesizing chiral allylic amides without the use of transition metal catalysts. Chiral binaphthol-catalyzed conjugate addition of alkenylboronates to -silyl--unsaturated ketones afforded highly enantioenriched chiral -silylcarbonyls. Asymmetric addition onto -silyl-enones is still a largely unexplored area, with only a handful of transition metal-catalyzed reactions reported. The first asymmetric reaction using these silicon-containing enones without using transition metal were described.