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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2009., Includes bibliographical references (p. 209-217)., Homogenous-charge, compression-ignition (HCCI) combustion is a new method of burning fuel in internal combustion (IC) engines. In an HCCI engine, the fuel and air are premixed prior to combustion, like in a spark-ignition (SI) engine. However, rather than using a spark to initiate combustion, the mixture is ignited through compression only, as in a compression-ignition (CI) engine; this makes combustion in HCCI engines much more sensitive to fuel chemistry than in traditional IC engines. The union of SI- and CI-technologies gives HCCI engines substantial efficiency and emissions advantages. However, one major challenge preventing significant commercialization of HCCI technology is its small operating range compared to traditional IC engines. This project examined the effects of fuel chemistry on the size of the HCCI operating region, with an emphasis on the low-load limit (LLL) of HCCI operability. If commercialized, HCCI engines will have to operate using standard commercial fuels. Therefore investigating the impact of fuel chemistry variations in commercial gasolines on the HCCI operability limits is critical to determining the fate of HCCI commercialization. To examine these effects, the operating ranges of 12 gasolines were mapped in a naturally-aspirated, single-cylinder HCCI engine, which used negative valve overlap to induce HCCI combustion. The fuels were blended from commercial refinery streams to span the range of market-typical variability in aromatic, ethanol, and olefin concentrations, RON, and volatility. The results indicated that all fuels achieved nearly equal operating ranges. The LLL of HCCI operability was completely insensitive to fuel chemistry, within experimental measurement error. The high-load limit showed minor fuel effects, but the trends in fuel performance were not consistent across all the speeds studied. These results suggest that fuel sensitivity is not an obstacle to auto-makers and/or fuel companies to introducing HCCI technology., (cont.) Developing an understanding of what causes an HCCI engine to misfire allows for estimation of how fuel chemistry and engine operating conditions affect the LLL. The underlying physics of a misfire were studied with an HCCI simulation tool (MITES), which used detailed chemical kinetics to model the combustion process. MITES was used to establish the minimum ignition temperature (Tmisfire) and full-cycle, steady-state temperature (Tss) for a fuel as a function of residual fraction. Comparison of Tmisfire and Tss near the misfire limit showed that Tss approaches Tmisfire quite closely (to within ~ 14 K), suggesting that the primary cause of a misfire is insufficient thermal energy needed to sustain combustion for multiple cycles. With this relationship, the effects of engine speed and fuel chemistry on the LLL were examined. Reducing the engine speed caused a reduction in T, which allowed fuel chemistry effects to be more apparent. This effect was also observed experimentally with 2 primary reference fuels (PRFs): PRF60 and PRF90. At 1000 RPM, PRF60 obtained a substantially lower (~30%) LLL than PRF90, but at speeds >/= 1500 RPM, fuel ignitability had no effect on the LLL. Fuel chemistry was shown to influence the LLL by increasing both Tmisfire and Tss for more auto-ignition resistant fuels. However, the extent to which fuel chemistry affects these temperatures may not be equivalent. Therefore, the relative movement of each temperature determines the extent to which fuel chemistry impacts the LLL., by John P. Angelos., Ph.D.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1995; and, Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1995., Includes bibliographical references., by John Novak., M.S.

Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering; in conjunction with the Leaders for Manufacturing Program at MIT, 2007., Includes bibliographical references (p. 55-56)., In early-stage drug discovery, thousands of compounds must be tested using in vitro assays to determine their exposure and safety characteristics. This data is used to guide the selection of potential drug candidates and to help chemists in optimize the properties of those compounds. At Novartis, an internal service organization called Preclinical Compound Profiling (PCP) provides these services to the company as a whole. The purpose of this internship was to help PCP make significant improvements in cycle time and cost effectiveness without reducing the quality of information provided to their customers. The project utilized a series of deterministic and stochastic models to predict the impact of multiple operational changes on cost and cycle time. The data from each model was synthesized to create a unified view allowing combinations of changes to be analyzed together. This data was evaluated in the context of the customer needs and organizational strategy to present recommendations. Changes were implemented that will reduce materials spending by $500,000 per year while simultaneously increasing capacity, reducing cycle time, and improving customer value. Additional recommendations were developed that will enable further improvements., by John P. Heiney., S.M., M.B.A.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2006., Vita., Includes bibliographical references., Quantum dot-based fluorescent probes were synthesized and applied to biological imaging in two distinct size regimes: (1) 100-1000 nm and (2) < 10 nm in diameter. The larger diameter range was accessed by doping CdSe/ZnS or CdS/ZnS quantum dots (QDs) into shells grown on the surfaces of pre-formed sub-micron SiO2 microspheres. The smaller diameter range was accessed with two different materials: very small InAs/ZnSe QDs and CdSe/ZnS QDs, each water solubilized with small molecule ligands chosen for their ability not only to stabilize QDs in water but also to minimize the total hydrodynamic size of the QD-ligand conjugates. Indium arsenide QDs were synthesized because nanocrystals of this material can be tuned to fluoresce in the near infrared (NIR) portion of the electromagnetic spectrum, especially in the 700-900 nm window where many tissues in the body absorb and scatter minimally, while maintaining core sizes of 2 nm or less. The QD-containing microspheres were used to image tumor vasculature in living animals, and to generate maps of size-dependent extravasation. With subcutaneously delivered nAs/ZnSe QDs, multiple lymph node mapping was demonstrated in vivo for the first time with nanocrystals. When administered intravenously, < 10 nm QDs escaped from the vasculature, or were efficiently cleared from circulation by the kidney. Both of these behaviors, previously unreported, mark key milestones in the realization of an ideal fluorescent QD probe for imaging specific compartments in vivo. Also presented in this thesis is the growth of single-crystalline cobalt nanorods through the oriented attachment of spherical cobalt nanocrystal monomers., (cont.) When administered intravenously, < 10 nm QDs escaped from the vasculature, or were efficiently cleared from circulation by the kidney. Both of these behaviors, previously unreported, mark key milestones in the realization of an ideal fluorescent QD probe for imaging specific compartments in vivo. Also presented in this thesis is the growth of single-crystalline cobalt nanorods through the oriented attachment of spherical cobalt nanocrystal monomers., by John P. Zimmer., Ph.D.

Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering; in conjunction with the Leaders for Manufacturing Program at MIT, 2004., Includes bibliographical references (p. 89-90)., As most companies in the consumer products space develop operational capabilities to produce and distribute high-quality low-cost products, leading firms in the industry continuously seek new ways to increase profitability and provide value to their retail partners and end consumers. While firms such as Procter & Gamble (P&G) have developed lean and flexible supply chains, this innovation has not had significant impact on the actual sale of product to the customer in individual stores. Analysis shows that large differences in the level of consumer demand for specific products exist across retail chains. However, current practices typically treat all stores across a chain the same. This thesis presents methods to target store-level marketing levers, including product mix, promotions, pricing, distribution and inventory management levels, based on shopper demographics and past purchasing behavior. Specifically, a framework to divide large retail chains into smaller "virtual chains" and subsequently develop targeted micro-marketing strategies for these virtual chains is presented. Research for this thesis was conducted during a six and a half month internship with P&G's Product Supply group at the Cosmetics division in Hunt Valley Maryland. The internship was affiliated with the Massachusetts Institute of Technology's Leaders for Manufacturing Program., by John P. Sharkey., S.M., M.B.A.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004., Includes bibliographical references., An in vivo flow cytometer has been developed that allows the real-time detection and quantification of circulating cells containing fluorescent proteins or labeled with fluorochrome molecules in live animals, without the need to extract blood samples. A stationary laser beam is focused by a cylindrical lens to a slit of light that is then demagnified and focused across a blood vessel by an achromat and microscope objective. Fluorescent cells are excited one by one as they flow through the excitation laser light slit, creating a burst of fluorescence whose width is inversely proportional to their velocity. The fluorescence signal is detected through a confocal slit aperture using a photomultiplier tube. The analog signal from the photomultiplier tube is then digitized, filtered, and recorded as a function of time onto a computer. Computer programs post- process the data for the presence of cell signal, as well as various aspects of the cell signal such as height, width, and temporal location of the signal peak. Two in vivo flow cytometers have been built: a single-slit, single-color system and a two- slit, two-color system. The single-slit, single-color system provides excitation at 632 nm, and the two-slit, two-color system provides excitation at 632 nm and 473 nm. The two- slit, two-color system can operate in several different modes: single-slit at 632 nm or 473 nm, double-slit at 632 nm or 473 nm, and double-slit with one excitation slit at 632 nm and the other at 473 nm., (cont.) Thus far, the single-slit, single-color system has been used to study the circulation kinetics of different prostate cancer and leukemia cell lines with different metastatic potential, as well as the effect of different host environments (i.e., mouse versus rat). In addition, the device has been used to develop a new in vivo labeling method of white blood cells that does not result in significant depletion of the labeled cells, allowing for the possibility of autoimmune and transplant rejection studies. The two-slit, two-color system is being used to track two different cell populations, or one cell population labeled with two different markers, one of which can be the green fluorescent protein., by John P. Novak., Ph.D.

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1999., Includes bibliographical references (p. 399-404)., An integral twist-actuated rotor blade has been developed for helicopter individual blade control (IBC) applications. A I/6th Mach scale CH-47D blade was designed, fabricated, and tested in hover at the MIT Hover Test Stand Facility. The design incorporates active fiber composite actuators (AFC) within the composite spar to induce a distributed twisting moment along the span. The anisotropic actuators are oriented at 45° to the blade axis to maximize the shear stresses generated. A baseline model blade was modified to obtain design targets of 4° of peak-to-peak tip twist, less than 20% added mass, matching stiff­ness properties with the exception of torsional stiffness, and ensuring adequate strength for forward flight. As a part of the development, active fiber composite (AFC) were subjected to structural integrity tests in order to optimize the material system and qualify the actuator for the rotor application. A new manufacturing process was developed for producing the actua­tors required for the integral blade. The capabilities of the actuators were defined and shown to be suitable for the integral blade application. Based on a passive model blade manufacturing procedure from Boeing, a manufacturing process was developed for the integral blade. The design and manufacture were validated and improved in three half-span blade section tests. With the final blade section, the twist actuation performance was demonstrated near predicted levels and damage tolerance was demonstrated in combined loading tests which simulated limit loads. The twist actuation performance of the active blade was evaluated over a range of rotor speeds, actuation frequencies, and blade loading conditions in hover. Transfer function data were collected from input voltage to blade twist and induced vertical hub shear. Changing test conditions had little affect on the measured performance, though blade flap­ping mode dynamics had a significant effect. Actuator electrical system failures limited t, by John P. Rodgers., Ph.D.

Thesis (Ph. D.)--Massachusetts Institute of Technology, Sloan School of Management, 1991., Includes bibliographical references (p. 443-459)., by John Pinckney Workman, Jr., Ph.D.

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1999., Includes bibliographical references., New methods for the palladium-catalyzed amination of aryl halides are described. Key to these is the development of new catalysts and reaction conditions for these transformations. Initially, P(o-tol)3 ligated palladium catalysts were investigated but gave way to systems that used chelating phosphine ligands which substantially expanded the scope of the catalytic amination methodology. Palladium catalyst systems based on BINAP ((2,2'-diphenylphosphino)-1, 1 '-binaphthyl) allowed for the transformation of a much wider range of amines and aryl halide substrates, as well as aryl triflates. Of practical significance was that the use of cesium carbonate as a base at 100 °C substantially increased the functional group tolerance of the method. Palladium catalysts supported by novel, bulky, electron-rich phosphine ligands are exceptionally effective in the C-N, C-0, and C-C coupling procedures. For some substrate combinations, these palladium catalysts are effective for the room-temperature catalytic amination of aryl chlorides. These palladium catalysts are also highly effective for Suzuki coupling reactions of aryl bromides and chlorides at room temperature. Suzuki coupling reactions of aryl bromides and aryl chlorides are effective at very low catalyst loadings (0.000001-0.005 mol % Pd for ArBr, 0.02-0.05 mol % for ArCI) at 100 °C, and reactions of hindered aryl halides or boronic acids are effected at moderate catalyst loadings (1 mol % Pd). The high reactivity of these catalysts towards aryl chlorides challenges the conventional dogma that chloride substrates cannot be transformed under mild conditions with palladium catalysts, and significantly expands the pool of substrates available for cross-coupling chemistry., by John P. Wolfe., Ph.D.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2002., Includes bibliographical references (p. 111)., Damping in MEMS resonators was studied experimentally and numerically. Quality factor measurements were performed on Draper gyroscopes made from boron doped silicon wafers with varying amount of germanium (0%, 2%, 23%, 30% ). The quality factors of gyroscopes with germanium were measured to be lower than those without germanium, due to increased anelastic damping. Specifically, the decreased thermal conductivity in the devices with germanium causes those devices to experience thermoelastic damping of a greater magnitude than the germanium-free devices. The amount of damping exhibited is found to be well explained by existing analytical expressions for thermoelastic dissipation in a beam model. The governing equations of thermo elasticity dictate that the amount of damping that a resonator undergoes is a function of both material properties as well as device geometry. Damping will become greatest at operating cycle times that are of the same scale as the thermal relaxation times of the device material. Due to the fact that analytical expressions exist for only a few simple geometries, a finite element model was developed to evaluate thermoelastic damping in more complicated geometries. The finite element model is demonstrated to be in good qualitative agreement with the analytical expressions, and is used to analyze the impact of design modifications such as the addition of fillets and anchors to a simple beam model. It is shown that depending on the size scale of the resonator (which dictates the amount of internal damping), these geometric modifications may either hinder or improve resonator damping characteristics., by John P. Gorman., S.M.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1995., Includes bibliographical references (p. 159-165)., by John P. Rodgers., M.S.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1994., Includes bibliographical references (p. 71)., by John P. Mann., M.S.

Thesis (S.M.)--Massachusetts Institute of Technology, System Design & Management Program, 2001., Includes bibliographical references (p. 85)., Knowledge Transfer is a generic term that is applicable to many domains. This thesis will analyze the specific issues required to develop a comprehensive framework for the assessment of knowledge transfer in the software development environment. Knowledge transfer is an essential component of all business processes in software development. The framework in this thesis was developed at a level of sufficient abstraction to be applicable to all software development activities. However, the research interviews focused on two scenarios in software development recognized as requiring effective knowledge transfer in order to achieve successful results: * Porting: A Porting project is an effort to enable a program to run on a different hardware or software platform. To port an application, you need to rewrite sections that are machine dependent, and then recompile the program on the new computer. The resultant code is then tested, often by some type of compliance suite, to insure that the ported product is operationally equivalent to the original product. When there is a market or business need, software products may be "ported" to new hardware/software platforms. A new team, with expertise in the new platform architecture, is usually called upon to do the porting. In order to optimize the port, knowledge from the original development team must be effectively transferred to the new organization. Service Transfer (maintenance) - Similar to the above, an software development organization will often transfer or assign responsibility for product service/maintenance to a separate service/support team. The ability to insure high-quality customer support requires a successful transfer of knowledge from the development group to the service/support group. This thesis provides a comprehensive framework for assessing a software development organization's knowledge transfer efforts and requirements. The framework presents a balanced approach introducing three columns of support for kno, by John P. Woods., S.M.

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1997., "September 1997.", Includes bibliographical references (leaves 83-84)., by John P. McMurray and Samuel M. Mundel., S.M.

Since its national debut in 1987, Fresh Air with Terry Gross has been a highly acclaimed and much adored weekday magazine among public radio listeners. Each week, nearly 4.8 million people turn to Peabody Award-winning host Terry Gross for insightful conversations with the leading voices in contemporary arts and issues. The renowned program reaches a global audience, with over 620 public radio stations broadcasting Fresh Air, and 3 million podcast downloads each week. Fresh Air has broken the mold of 'talk show' by weaving together superior journalism and intimate storytelling from modern-day intellectuals, politicians and artists alike. Through probing questions and careful research, Gross's interviews are lauded for revealing a fresh perspective on cultural icons and trends. Her thorough conversations are often complemented by commentary from well-known contributors. Fresh Air is produced at WHYY-FM in Philadelphia and broadcast nationally by NPR., INT. 1: JOHN PERRY BARLOW is the co-founder of the Electronic Frontier Foundation, which defends civil liberties in cyberspace. BARLOW is also a former cattle rancher in Wyoming, and a former lyricist for the Grateful Dead. The Electronic Frontier Foundation is located at 1667 K St. NW, Suite 801, Washington, D.C. 20006-1605. (THIS INTERVIEW CONTINUES INTO THE SECOND HALF OF THE SHOW). INT. 1a Interview with JOHN PERRY BARLOW continued. INT. 2: Independent film director, writer and editor MARK RAPPAPORT. His newest film is "From the Journals of Jean Seberg," about the actress Jean Seberg. The movie is a "fictitious autobiography" and places Seberg's life and work in a political context of the 1960s. Seberg's life ended in a tragic suicide. She grew up in Iowa, was best known for her role in Jean Luc Godard's "Breathless," and Otto Preminger's "Saint Joan." In the 60s she got involved with the Black Panthers. The film stars Mary Beth Hurt as Seberg, and also uses footage and photos of Seberg. INT. 2A: Interview with MARK RAPPAPORT continued.