Productivity improvement in downstream EPC projects using value streams based organization

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, 2006.Includes bibliographical references (p. 82).Productivity improvements in manufacturing facilities have been studied in detail and there are many standardized tools and frameworks readily available to the industry for implementation. However the concept of productivity improvement in large engineering projects that involve high white-collar job content is less clearly understood. While lean concepts like value streams or continuous improvement apply to this environment there are no ready tools available for implementing a lean improvement initiative. This thesis applies lean and concurrent engineering concepts to large scale engineering design and development projects. ABB Lummus, the sponsor company for the internship behind this thesis, is in the business of executing such large-scale projects. Lummus is an EPC contractor providing engineering, procurement and construction (EPC) services for building manufacturing plants. EPC projects run for few years and involve coordination of efforts by hundreds of engineering staff. There are inherently many productivity and information flow issues in such projects. EPC industry in general has been facing significant operational efficiency difficulties leading to cost and schedule overruns in recent years.(cont.) The main issue was identified as rework due to the fact that the existing project structures do not deal with concurrent engineering nature of the projects. In this thesis we leverage the concepts a combination of lean value streams, Design Structure Matrix (DSM) and Theory of Constraints (TOC) to propose a value streams based organization for EPC projects. We show how this approach addresses the common problem in the EPC projects and sets the stage for improving productivity. The discussion in this thesis has helped launch an initiative that has enabled the acceptance of value streams and DSM techniques at ABB Lummus. Currently a dedicated program is planning a large (> 1 Bn Euro) EPC project along the line of value streams. The following are the key contributions in this thesis: From first principles we define a way to decompose an EPC downstream project into nine value streams. We use DSM to analyze a key value stream in detail and show the need for a value-stream-based organization. Using value streams and DSM we enable the implementation of TOC planning in EPC projects and show how these tools complement each other.by Krishnan Raghunathan.S.M.M.B.A

Evidence of a Double-Lid Movement in Pseudomonas aeruginosa Lipase: Insights from Molecular Dynamics Simulations

Pseudomonas aeruginosa lipase is a 29-kDa protein that, following the determination of its crystal structure, was postulated to have a lid that stretched between residues 125 and 148. In this paper, using molecular dynamics simulations, we propose that there exists, in addition to the above-mentioned lid, a novel second lid in this lipase. We further show that the second lid, covering residues 210–222, acts as a triggering lid for the movement of the first. We also investigate the role of hydrophobicity in the movement of the lids and show that two residues, Phe214 and Ala217, play important roles in lid movement. To our knowledge, this is the first time that a double-lid movement of the type described in our manuscript has been presented to the scientific community. This work also elucidates the interplay of hydrophobic interactions in the dynamics, and hence the function, of an enzyme

Distribution and Habitat Use by Asian Elephants (Elephas maximus) in a Coffee-Dominated Landscape of Southern India

Understanding the impacts of land-use mosaics on elephant distribution and the patterns of habitat use is essential for their conservation in modified landscapes. We carried out a study in 205 villages, covering 610 km2 of plantation–agriculture–forest mosaic of Hassan–Madikeri divisions in southern India, an area of intense human–elephant interactions. We monitored elephant movements, crop damage incidents, and human casualties on a daily basis for a 2-year period (2015–2017) to understand the patterns of elephant distribution across the landscape and habitat-use patterns, resulting in 1,117 GPS locations across six major habitats. Elephants were distributed across the landscape in the first year, but a high concentration of locations were noticed toward northern part of the study area during the second year, owing to clear felling of trees and installation of barriers around coffee plantations, causing an overall shift in their distribution. Investigations into habitat use by elephants revealed that during the day, elephants preferred monoculture refuges of acacia, eucalyptus, and so on, and forest fragments, avoiding reservoir, coffee, roads, and habitations. At night, agricultural lands were used more frequently while moving between refuges compared with forest fragments and habitations. Seasonally, forest fragments and agriculture were used significantly more during dry and wet, respectively. Across years, use of monoculture refuges and coffee increased with a corresponding decrease in the use of forest fragments and agriculture. In areas devoid of forest habitats, retention of monoculture refuges which provide shelter for elephants and facilitating free movement through open habitats may help minimize human–elephant conflict and promote coexistence in such land-use mosaics

Towards Upcycling Biomass-Derived Crosslinked Polymers with Light

Photodegradable, recyclable, and renewable, crosslinked polymers from bioresources show promise towards developing a sustainable strategy to address the issue of plastics degradability and recyclability. Photo processes are not widely exploited for upcycling polymers in spite of the potential to have spatial and temporal control of the degradation in addition to being a green process. In this report we highlight a methodology in which biomass-derived crosslinked polymers can be programmed to degrade at ≈300 nm with ≈60 % recovery of the monomer. The recovered monomer was recycled back to the crosslinked polymer

Friction Mediates Scission of Tubular Membranes Scaffolded by BAR Proteins

International audienceMembrane scission is essential for intracellular trafficking. While BAR domain proteins such as endophilin have been reported in dynamin-independent scission of tubular membrane necks, the cutting mechanism has yet to be deciphered. Here, we combine a theoretical model, in vitro, and in vivo experiments revealing how protein scaffolds may cut tubular membranes. We demonstrate that the protein scaffold bound to the underlying tube creates a frictional barrier for lipid diffusion; tube elongation thus builds local membrane tension until the membrane undergoes scission through lysis. We call this mechanism friction-driven scission (FDS). In cells, motors pull tubes, particularly during endocytosis. Through reconstitution, we show that motors not only can pull out and extend protein-scaffolded tubes but also can cut them by FDS. FDS is generic, operating even in the absence of amphipathic helices in the BAR domain, and could in principle apply to any high-friction protein and membrane assembly

Towards personalized data-driven bundle design with QoS constraint

Singapore National Research Foundation under its International Research Centre @ Singapore Funding Initiativ

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Effects of antiplatelet therapy after stroke due to intracerebral haemorrhage (RESTART): a randomised, open-label trial

Background: Antiplatelet therapy reduces the risk of major vascular events for people with occlusive vascular disease, although it might increase the risk of intracranial haemorrhage. Patients surviving the commonest subtype of intracranial haemorrhage, intracerebral haemorrhage, are at risk of both haemorrhagic and occlusive vascular events, but whether antiplatelet therapy can be used safely is unclear. We aimed to estimate the relative and absolute effects of antiplatelet therapy on recurrent intracerebral haemorrhage and whether this risk might exceed any reduction of occlusive vascular events. Methods: The REstart or STop Antithrombotics Randomised Trial (RESTART) was a prospective, randomised, open-label, blinded endpoint, parallel-group trial at 122 hospitals in the UK. We recruited adults (≥18 years) who were taking antithrombotic (antiplatelet or anticoagulant) therapy for the prevention of occlusive vascular disease when they developed intracerebral haemorrhage, discontinued antithrombotic therapy, and survived for 24 h. Computerised randomisation incorporating minimisation allocated participants (1:1) to start or avoid antiplatelet therapy. We followed participants for the primary outcome (recurrent symptomatic intracerebral haemorrhage) for up to 5 years. We analysed data from all randomised participants using Cox proportional hazards regression, adjusted for minimisation covariates. This trial is registered with ISRCTN (number ISRCTN71907627). Findings: Between May 22, 2013, and May 31, 2018, 537 participants were recruited a median of 76 days (IQR 29–146) after intracerebral haemorrhage onset: 268 were assigned to start and 269 (one withdrew) to avoid antiplatelet therapy. Participants were followed for a median of 2·0 years (IQR [1·0– 3·0]; completeness 99·3%). 12 (4%) of 268 participants allocated to antiplatelet therapy had recurrence of intracerebral haemorrhage compared with 23 (9%) of 268 participants allocated to avoid antiplatelet therapy (adjusted hazard ratio 0·51 [95% CI 0·25–1·03]; p=0·060). 18 (7%) participants allocated to antiplatelet therapy experienced major haemorrhagic events compared with 25 (9%) participants allocated to avoid antiplatelet therapy (0·71 [0·39–1·30]; p=0·27), and 39 [15%] participants allocated to antiplatelet therapy had major occlusive vascular events compared with 38 [14%] allocated to avoid antiplatelet therapy (1·02 [0·65–1·60]; p=0·92). Interpretation: These results exclude all but a very modest increase in the risk of recurrent intracerebral haemorrhage with antiplatelet therapy for patients on antithrombotic therapy for the prevention of occlusive vascular disease when they developed intracerebral haemorrhage. The risk of recurrent intracerebral haemorrhage is probably too small to exceed the established benefits of antiplatelet therapy for secondary prevention