Finding an upper bound on the increase in execution time due to contention on the memory bus in COTS-based multicore systems

Contention on the memory bus in COTS based multicore systems is becoming a major determining factor of the execution time of a task. Analyzing this extra execution time is non-trivial because (i) bus arbitration protocols in such systems are often undocumented and (ii) the times when the memory bus is requested to be used are not explicitly controlled by the operating system scheduler; they are instead a result of cache misses. We present a method for finding an upper bound on the extra execution time of a task due to contention on the memory bus in COTS based multicore systems. This method makes no assumptions on the bus arbitration protocol (other than assuming that it is work-conserving).

INFO2009 Framework for Critical Friends Interaction

Guidance document detailing the suggested process for the critical friend team interaction

Sustaining Success Links and Readings

Links to video's (wip)

Sustaining Success Task: Week 3 Introduction to reflection

An introduction to a method of reflection. This task looks at the process of writing a short piece of reflection and provides a framework for that activity

Greenhouse gas emissions from waste management—assessment of quantification methods

Of the many sources of urban greenhouse gas (GHG) emissions, solid waste is the only one for which management decisions are undertaken primarily by municipal governments themselves and is hence often the largest component of cities’ corporate inventories. It is essential that decision-makers select an appropriate quantification methodology and have an appreciation of methodological strengths and shortcomings. This work compares four different waste emissions quantification methods, including Intergovernmental Panel on Climate Change (IPCC) 1996 guidelines, IPCC 2006 guidelines, U.S. Environmental Protection Agency (EPA) Waste Reduction Model (WARM), and the Federation of Canadian Municipalities- Partners for Climate Protection (FCM-PCP) quantification tool. Waste disposal data for the greater Toronto area (GTA) in 2005 are used for all methodologies; treatment options (including landfill, incineration, compost, and anaerobic digestion) are examined where available in methodologies. Landfill was shown to be the greatest source of GHG emissions, contributing more than three-quarters of total emissions associated with waste management. Results from the different landfill gas (LFG) quantification approaches ranged from an emissions source of 557 kt carbon dioxide equivalents (CO2e) (FCM-PCP) to a carbon sink of −53 kt CO2e (EPA WARM). Similar values were obtained between IPCC approaches. The IPCC 2006 method was found to be more appropriate for inventorying applications because it uses a waste-in-place (WIP) approach, rather than a methane commitment (MC) approach, despite perceived onerous data requirements for WIP. MC approaches were found to be useful from a planning standpoint; however, uncertainty associated with their projections of future parameter values limits their applicability for GHG inventorying. MC and WIP methods provided similar results in this case study; however, this is case specific because of similarity in assumptions of present and future landfill parameters and quantities of annual waste deposited in recent years being relatively consistent.

Why initial conditions are important

Most simulation textbooks assume that a model can be started in an empty state and the final output will not be affected, so long as the "warm-up period" is excluded from the analysis. In this paper we test this assumption, using a discrete-event model of a existing manufacturing facility. Using a series of model runs with no initial Work in Progress (WIP) and another series of simulation runs with a realistic initial level of WIP, the results can be compared and contrasted. While the results show similar shaped profiles in terms of throughput and lead time, the differences between the curves has important practical implications.

Using bottlenecks to control production inventory

In this paper, we investigate how to best optimise the level of Production Inventory or Work In Progress (WIP) in a factory. Using a simulation model of the factory, we show that a level of inventory can be optimised by controlling the buffer levels of the key bottleneck workcenters. By firstly identifying the key bottlenecks, and then systematically reducing the maximum buffer level for each bottleneck, results show that the throughput does not drop rapidly from it's high levels until the WIP is halved. Conversely, the production lead time decreases rapidly and levels out around the point of the optimum WIP level.

On work in progress optimisation

In this paper, we investigate how to best optimise the level of work in progress (WIP) in a real world factory. Using a simulation model of the factory, we show that an optimum level of WIP can be attained. By systematically varying the maximum allowable level of WIP within different model runs, results show that the throughput reaches a high level very quickly and then tapers off. The production lead times, in contrast, begin at relatively low levels and increase after the optimum WIP level has been reached.

Development of an optimum factory model for a manufacturing operation through computer simulation

Often manufacturing enterprises will maintain high levels of Work In Progress (WIP) to maximise production throughput. Using computer simulation, this thesis investigates a manufacturing facility and identifies an optimal level of WIP. At this optimum throughput is maximised, manufacturing lead times are minimised, and the WIP level is significantly reduced.

Conceitos de gestão de projetos e teoria das restrições, aplicados ao planejamento e controle da produção de uma empresa aeronaútica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Analisi del flusso del valore e razionalizzazione delle aree di stoccaggio per una linea di produzione: Il caso Ducati Motor Holding

Value Stream Mapping di un flusso di produzione in un reparto di lavorazioni meccaniche. Riduzione del Working Capital tramite livelellamento della produzione per la riduzione del lotto medio. Analisi e razionalizzazione dei magazzini interoperazionali.

Empirische Evidenz der INT

Die INT wurde in einer randomisierten, internationalen Multicenterstudie in der Schweiz, Deutschland und Österreich evaluiert und vom Schweizerischen Nationalfonds unterstützt (Projektnummer 3200 B0‑108133). Insgesamt nahmen 169 Personen an der Studie teil. Personen wurden in die Studie eingeschlossen, wenn sie die Diagnosekriterien für eine schizophrene oder schizoaffektive Erkrankung gemäß ICD‑10 oder DSM-IV‑R erfüllten, in ambulanter oder teilstationärer Behandlung waren, ein Alter zwischen 18 und 50 Jahren sowie eine Krankheitsdauer von mehr als zwei Jahren aufwiesen und einen Intelligenzquotienten über 80 erreichten (Reduzierter Wechsler Intelligenztest, WIP). Ausschlusskriterien waren eine akute psychotische Episode, eine primäre Substanzabhängigkeit sowie eine hirnorganische Erkrankung.

High exchangeable calcium concentrations in soils on Barro Colorado Island, Panama

The soils on four lithologies (basaltic conglomerates, Bohio; Andesite; volcanoclastic sediments with basaltic agglomerates, Caimito volcanic; foraminiferal limestone, Caimito marine) on Barro Colorado Island (BCI) have high exchangeable Ca concentrations and cation-exchange capacities (CEC) compared to other tropical soils on similar parent material. In the 0–10 cm layer of 24 mineral soils, pH values ranged from 5.7 (Caimito volcanic and Andesite) to 6.5 (Caimito marine), concentrations of exchangeable Ca from 134 mmolc kg− 1 (Caimito volcanic) to 585 mmolc kg− 1 (Caimito marine), and cation exchange capacities from 317 mmolc kg− 1 (Caimito volcanic) to 933 mmolc kg− 1 (Caimito marine). X-ray diffractometry of the fraction < 2 μm revealed that smectites dominated the clay mineral assemblage in soil except on Caimito volcanic, where kaolinite was the dominant clay mineral. Exchangeable Ca concentrations decreased with increasing soil depth except on Caimito marine. The weathering indices Chemical Index of Alteration (CIA), Plagioclase Index of Alteration (PIA) and Weathering Index of Parker (WIP) determined for five soils on all geological formations, suggested that in contrast to expectation the topsoil (0–10 cm) appeared to be the least and the subsoil (50–70 cm) and saprolite (isomorphically weathered rock in the soil matrix) the most weathered. Additionally, the weathering indices indicated depletion of base cations and enrichment of Al-(hydr)oxides throughout the soil profile. Tree species did not have an effect on soil properties. Impeded leaching and the related occurrence of overland flow seem to be important in determining clay mineralogy. Our results suggest that (i) edaphic conditions favor the formation of smectites on most lithologies resulting in high CEC and thus high retention capacity for Ca and (ii) that there is an external source such as dust or sea spray deposition supplying Ca to the soils.

Change in physiotherapy management of children with cystic fibrosis in a large urban hospital

A retrospective audit was conducted in 1998 and 2000 to review the physiotherapy management of hospitalized children with cystic fibrosis (CF) at the Brisbane Royal Children's Hospital (RCH). The objective was to detect and explore possible changes in patient management in this time period and investigate whether these changes reflected changes in the current theory of CF management. All children over two years of age with CF admitted during 1998 and 2000 with pulmonary manifestation and who satisfied set criteria were included (n = 249). Relative frequency of each of six treatment modalities used were examined on two occasions, revealing some degree of change in practice reflecting the changes in current theory. There was a significant decrease in the frequency of usage of postural drainage with head-down tilt (p < 0.001), and autogenic drainage (p < 0.001) between 1998 and 2000. Modified postural drainage without head-down tilt (p < 0.001), and positive expiratory pressure devices (p < 0.001) were used more frequently in 2000 (p < 0.001). No significant changes were identified in the use of Flutter VRP1 (p = 0.145) and exercise (p = 0.763). No significant differences were found in population demographics or occurrence of concomitant factors that may influence patient management.

A simulation study of the shift system at a UK police communications centre

The UK Police Force is required to operate communications centres under increased funding constraints. Staff represent the main cost in operating the facility and the key issue for the efficient deployment of staff, in this case call handler staff, is to try to ensure sufficient staff are available to make a timely response to customer calls when the timing of individual calls is difficult to predict. A discrete-event simulation study is presented of an investigation of a new shift pattern for call handler staff that aims to improve operational efficiency. The communications centre can be considered a specialised case of a call centre but an important issue for Police Force management is the particularly stressful nature of the work staff are involved with when responding to emergency calls. Thus decisions regarding changes to the shift system were made in the context of both attempting to improve efficiency by matching staff supply with customer demand, but also ensuring a reasonable workload pattern for staff over time.