Enabling waste elimination, learning, and continuous improvement through standardization

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, 2005.Includes bibliographical references (leaf 92).Many manufacturing companies have developed their own operating system, usually based upon the Toyota Production System, in an effort to improve productivity, quality, and profitability. Continuous improvement is a central theme to most operating systems. Typically large continuous improvement projects or kaizen bursts are used to improve processes. However, these often lead to variable and unsustainable results. A hypothesis is that a detailed standardization of processes will enable opportunities to be quickly revealed. Then a focus on incremental improvement through experimentation can lead to dramatic sustainable results. This thesis is based upon my experience at Mighty Motors in an attempt to gain a deeper understanding about standardization and continuous improvement. I obtained this understanding through direct observation by working with operators on the assembly line to standardize the process and make improvements. I developed the following conclusions: Focus on standardization to achieve sustainable continuous improvement. Without standardization, randomness and variability will hide the wastes and improvements will deteriorate.(cont.) Value the incremental improvement approach to continuous improvement. Through simple, common-sense, and low cost experimentation a great deal of process improvements can be made. Creating an organization that values standardization and continuous improvement is the hard part. This involves more than using a set of problem solving tools.by Mark E. Stover.S.M.M.B.A

Search for intermediate-mass black hole binaries in the third observing run of Advanced LIGO and Advanced Virgo

International audienceIntermediate-mass black holes (IMBHs) span the approximate mass range 100−105 M⊙, between black holes (BHs) that formed by stellar collapse and the supermassive BHs at the centers of galaxies. Mergers of IMBH binaries are the most energetic gravitational-wave sources accessible by the terrestrial detector network. Searches of the first two observing runs of Advanced LIGO and Advanced Virgo did not yield any significant IMBH binary signals. In the third observing run (O3), the increased network sensitivity enabled the detection of GW190521, a signal consistent with a binary merger of mass ∼150 M⊙ providing direct evidence of IMBH formation. Here, we report on a dedicated search of O3 data for further IMBH binary mergers, combining both modeled (matched filter) and model-independent search methods. We find some marginal candidates, but none are sufficiently significant to indicate detection of further IMBH mergers. We quantify the sensitivity of the individual search methods and of the combined search using a suite of IMBH binary signals obtained via numerical relativity, including the effects of spins misaligned with the binary orbital axis, and present the resulting upper limits on astrophysical merger rates. Our most stringent limit is for equal mass and aligned spin BH binary of total mass 200 M⊙ and effective aligned spin 0.8 at 0.056 Gpc−3 yr−1 (90% confidence), a factor of 3.5 more constraining than previous LIGO-Virgo limits. We also update the estimated rate of mergers similar to GW190521 to 0.08 Gpc−3 yr−1.Key words: gravitational waves / stars: black holes / black hole physicsCorresponding author: W. Del Pozzo, e-mail: [email protected]† Deceased, August 2020