Optimized group replacement scheduling for water pipeline network

Replacement of deteriorated water pipes is a capital-intensive activity for utility companies. Replacement planning aims to minimize total costs while maintaining a satisfactory level of service and is usually conducted for individual pipes. Scheduling replacement in groups is seen to be a better method and has the potential to provide benefits such as the reduction of maintenance costs and service interruptions. However, developing group replacement schedules is a complex task and often beyond the ability of a human expert, especially when multiple or conflicting objectives need to be catered for, such as minimization of total costs and service interruptions. This paper describes the development of a novel replacement decision optimization model for group scheduling (RDOM-GS), which enables multiple group-scheduling criteria by integrating new cost functions, a service interruption model, and optimization algorithms into a unified procedure. An industry case study demonstrates that RDOM-GS can improve replacement planning significantly and reduce costs and service interruptions.

Multifaceted Modelling of Complex Business Enterprises

We formalise and present a new generic multifaceted complex system approach for modelling complex business enterprises. Our method has a strong focus on integrating the various data types available in an enterprise which represent the diverse perspectives of various stakeholders. We explain the challenges faced and define a novel approach to converting diverse data types into usable Bayesian probability forms. The data types that can be integrated include historic data, survey data, and management planning data, expert knowledge and incomplete data. The structural complexities of the complex system modelling process, based on various decision contexts, are also explained along with a solution. This new application of complex system models as a management tool for decision making is demonstrated using a railway transport case study. The case study demonstrates how the new approach can be utilised to develop a customised decision support model for a specific enterprise. Various decision scenarios are also provided to illustrate the versatility of the decision model at different phases of enterprise operations such as planning and control.

Beth Israel Hospital (Boston, MA) Records, undated, 1923, 1930-1964, 1988, 1991-1992

In 1916, the Jewish community of Boston established Beth Israel Hospital on Townsend Street in Roxbury to provide health care to immigrants in the area. Although accessible to everyone, the hospital provided Yiddish-speaking services for Eastern European Jewish immigrants and served kosher food, as well as conducted Jewish religious services. In 1928 the hospital entered into a teaching agreement with Harvard Medical School, Tufts University, and Simmons College. Shortly thereafter, the hospital moved to its current location in the Longwood area of Boston and expanded to a 220-bed operation. During 1935-1936, at the height of the Depression, Beth Israel spent 1.5 million dollars in free patient care and was only one of two local hospitals to offer health care to people on welfare. In 1996, Beth Israel Hospital merged with Deaconess Medical Center and became Beth Israel Deaconess Medical Center. This collection contains reports, pamphlets and hospital publications.

A data fusion approach of multiple maintenance data sources for real-world reliability modelling

A central tenet in the theory of reliability modelling is the quantification of the probability of asset failure. In general, reliability depends on asset age and the maintenance policy applied. Usually, failure and maintenance times are the primary inputs to reliability models. However, for many organisations, different aspects of these data are often recorded in different databases (e.g. work order notifications, event logs, condition monitoring data, and process control data). These recorded data cannot be interpreted individually, since they typically do not have all the information necessary to ascertain failure and preventive maintenance times. This paper presents a methodology for the extraction of failure and preventive maintenance times using commonly-available, real-world data sources. A text-mining approach is employed to extract keywords indicative of the source of the maintenance event. Using these keywords, a Naïve Bayes classifier is then applied to attribute each machine stoppage to one of two classes: failure or preventive. The accuracy of the algorithm is assessed and the classified failure time data are then presented. The applicability of the methodology is demonstrated on a maintenance data set from an Australian electricity company.

Ma Ma Ma Mad

Ma Ma Ma Mad is an autobiographical work, written and performed by Singaporean-Australian theatre maker Merlynn Tong. This production, presented at the Brisbane Powerhouse in December 2015, was a multi-genre work incorporating aspects of Butoh, physical theatre, cabaret and contemporary monologue. More than an experiment in mixed performative forms, however, this particular production was also an exercise in inter-cultural collaboration as well as gender in (and of) performance. Heavily influenced by the creator's experiences growing up in urban Southeast Asia, the director's specialisation in contemporary Australian theatre and experience telling uniquely Australian stories worked to manipulate the form in an endeavour to succinctly speak to local audiences, without pandering to entrenched stereotypes or diluting the underlying Chinese-Singaporean themes. The success of this production was also somewhat of a personal challenge for the creatives, after being told by some of Brisbane's most influential theatre venues and festivals that they would rather not support the work because a) it was a one woman show, and b) it was a one woman show about an Asian woman; and therefore would not sell well. One very influential local producer even said that he already had a one-woman show about an Asian person programmed, so he couldn't possibly program another. Operating in such a biased and out-of-touch artistic environment was seen as an easy challenge for the artists involved, which resulted in a highly successful and critically acclaimed sell-out run of Ma Ma Ma Mad, followed by offers to tour the work nationally and internationally. As such, this production also stands as a practical example of the ingrained and patriarchal structures of the Australian arts scene, and how art can work to break down the very barriers that it has helped to construct through a lack of vision and diversity amongst its leaders.

3D Fe2(MoO4)3 microspheres with nanosheet constituents as high-capacity anode materials for lithium-ion batteries

Three-dimensional (3D) Fe2(MoO4)3 microspheres with ultrathin nanosheet constituents are first synthesized as anode materials for the lithium-ion battery. It is interesting that the single-crystalline nanosheets allow rapid electron/ion transport on the inside, and the high porosity ensures fast diffusion of liquid electrolyte in energy storage applications. The electrochemical properties of Fe2(MoO4)3 as anode demonstrates that 3D Fe2(MoO4)3 microspheres deliver an initial capacity of 1855 mAh/g at a current density of 100 mA/g. Particularly, when the current density is increased to 800 mA/g, the reversible capacity of Fe2(MoO4)3 anode still arrived at 456 mAh/g over 50 cycles. The large and reversible capacities and stable charge–discharge cycling performance indicate that Fe2(MoO4)3 is a promising anode material for lithium battery applications. Graphical abstract The electrochemical properties of Fe2(MoO4)3 as anode demonstrates that 3D Fe2(MoO4)3 microspheres delivered an initial capacity of 1855 mAh/g at a current density of 100 mA/g. When the current density was increased to 800 mA/g, the Fe2(MoO4)3 still behaved high reversible capacity and good cycle performance.

Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics

A detailed study is presented of the expected performance of the ATLAS detector. The reconstruction of tracks, leptons, photons, missing energy and jets is investigated, together with the performance of b-tagging and the trigger. The physics potential for a variety of interesting physics processes, within the Standard Model and beyond, is examined. The study comprises a series of notes based on simulations of the detector and physics processes, with particular emphasis given to the data expected from the first years of operation of the LHC at CERN.

Hot deformation characteristics of INCONEL alloy MA 754 and development of a processing map

The characteristics of hot deformation of INCONEL alloy MA 754 have been studied processing maps obtained on the basis of flow stress data generated in compression in the temperature range 700-degrees-C to 1150-degrees-C and strain rate range 0.001 to 100 s-1. The map exhibited three domains. (1) A domain of dynamic recovery occurs in the temperature range 800-degrees-C to 1075-degrees-C and strain rate range 0.02 to 2 s-1, with a peak efficiency of 18 pct occurring at 950-degrees-C and 0.1 s-1. Transmission electron microscope (TEM) micrographs revealed stable subgrain structure in this domain with the subgrain size increasing exponentially with an increase in temperature. (2) A domain exhibiting grain boundary cracking occurs at temperatures lower than 800-degrees-C and strain rates lower than 0.01 s-1. (3) A domain exhibiting intense grain boundary cavitation occurs at temperatures higher than 1075-degrees-C. The material did not exhibit a dynamic recrystallization (DRX) domain, unlike other superalloys. At strain rates higher than about 1 s-1, the material exhibits flow instabilities manifesting as kinking of the elongated grains and adiabatic shear bands. The material may be safely worked in the domain of dynamic recovery but can only be statically recrystallized.

Multispecies coexistence of trees in tropical forests: spatial signals of topographic niche differentiation increase with environmental heterogeneity

Neutral and niche theories give contrasting explanations for the maintenance of tropical tree species diversity. Both have some empirical support, but methods to disentangle their effects have not yet been developed. We applied a statistical measure of spatial structure to data from 14 large tropical forest plots to test a prediction of niche theory that is incompatible with neutral theory: that species in heterogeneous environments should separate out in space according to their niche preferences. We chose plots across a range of topographic heterogeneity, and tested whether pairwise spatial associations among species were more variable in more heterogeneous sites. We found strong support for this prediction, based on a strong positive relationship between variance in the spatial structure of species pairs and topographic heterogeneity across sites. We interpret this pattern as evidence of pervasive niche differentiation, which increases in importance with increasing environmental heterogeneity.

Scale-dependent relationships between tree species richness and ecosystem function in forests

1. The relationship between species richness and ecosystem function, as measured by productivity or biomass, is of long-standing theoretical and practical interest in ecology. This is especially true for forests, which represent a majority of global biomass, productivity and biodiversity. 2. Here, we conduct an analysis of relationships between tree species richness, biomass and productivity in 25 forest plots of area 8-50ha from across the world. The data were collected using standardized protocols, obviating the need to correct for methodological differences that plague many studies on this topic. 3. We found that at very small spatial grains (0.04ha) species richness was generally positively related to productivity and biomass within plots, with a doubling of species richness corresponding to an average 48% increase in productivity and 53% increase in biomass. At larger spatial grains (0.25ha, 1ha), results were mixed, with negative relationships becoming more common. The results were qualitatively similar but much weaker when we controlled for stem density: at the 0.04ha spatial grain, a doubling of species richness corresponded to a 5% increase in productivity and 7% increase in biomass. Productivity and biomass were themselves almost always positively related at all spatial grains. 4. Synthesis. This is the first cross-site study of the effect of tree species richness on forest biomass and productivity that systematically varies spatial grain within a controlled methodology. The scale-dependent results are consistent with theoretical models in which sampling effects and niche complementarity dominate at small scales, while environmental gradients drive patterns at large scales. Our study shows that the relationship of tree species richness with biomass and productivity changes qualitatively when moving from scales typical of forest surveys (0.04ha) to slightly larger scales (0.25 and 1ha). This needs to be recognized in forest conservation policy and management.

Direct Numerical Simulation of a Spatially Evolving Supersonic Turbulent Boundary Layer at Ma=6

Direct numerical simulation is carried out for a spatially evolving supersonic turbulent boundary layer at free-stream Mach number 6. To overcome numerical instability, the seventh-order WENO scheme is used for the convection terms of Navier-Stokes equations, and fine mesh is adopted to minimize numerical dissipation. Compressibilty effects on the near-wall turbulent kinetic energy budget are studied. The cross-stream extended self-similarity and scaling exponents including the near-wall region are studied. In high Mach number flows, the coherence vortex structures are arranged to be smoother and streamwised, and the hair-pin vortices are less likely to occur.

Coherent Structures in Transition of a Flat-Plate Boundary Layer at Ma=0.7

Direct numerical simulation (DNS) of a spatially evolving flat-plate boundary layer transition process at free stream Mach number 0.7 is performed. Tollmien-Schlichting (T-S) waves are added on the inlet boundary as the disturbances before transition. Typical coherent structures in the transition process are investigated based on the second invariant of velocity gradient tensor. The instantaneous shear stress and the mean velocity profile in the transition region are studied. In our view, the fact that the peak value of shear stress in the stress concentration area increases and exceeds a threshold value during the later stage of the transition process plays an important role in the laminar breakdown process.

Barium-Functionalized Multiwalled Carbon Nanotube Yarns As Low-Work-Function Thermionic Cathodes

Barium-functionalized multiwalled carbon nanotube yarns were fabricated by drawing and twisting multiwalled carbon nanotube forests through a solution containing barium nitrate. After heat activation under vacuum, the functionalized yarns were enriched in barium oxide due to the high surface-to-volume ratio of the nanotubes. The cathodes exhibited good thermionic properties, with a work function as low as 1.73-2.06 eV and thermionic current density that exceeded 185 mA/cm(2) in a field of 850 V/5 mm at 1317 K. The barium-functionalized yarns had high tensile strength of up to 420 MPa and retained strength of similar to 250 MPa after a 2 h activation process. (C) 2008 American Institute of Physics.

Prueba de dos insecticidas sistémicos en dos formas de aplicación, en el control del tórsalo (Dermatobia hominis) Lin. Jr

Con el objeto de determinar cuál es el insecticida más efectivo en el control del tórsalo y la mejor forma de aplicación, se llevo a cabo un experimento en el Departamento de Boaco en el lapso comprendido de Julio a Diciembre de 1967. En cada finca se utilizaron cuarenta animales. Los insecticidas aplicados fueron: Ruelene 25 E en dosis de diez y siete miligramos por kilogramo de peso vivo y Neguvón en dosis de cincuenta miligramos por kilogramo de peso vivo. Los insecticidas se aplicaron en la forma siguiente: Ruelene 25 E vertido Ruelene 25 E solución Neguvón vertido Neguvón solución Se efectuaron recuentos de parásitos al principio del experimento y a los tres días y a los ocho días después de la aplicación de los insecticidas. El diseño experimental usado fue de bloques al azar con repeticiones y análisis dentro de las fincas. Los dos insecticidas y sus formas de aplicación estadísticamente tuvieron la misma efectividad, con porcentajes de control similares. el ruelene 25 E fue el insecticida de menor costo, en las dos formas de aplicación. Durante el experimento no se observaron efectos tóxicos en ningún animal. Se observó que el poder residual del Ruelene 25 E fue mayor que el del Neguvón.