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As the number of people affected by disasters globally continues to grow, preparedness and ‘last mile’ operational assistance must be adaptable and connections with the commercial world maximised

This paper reports on an investigation into factors affecting planning effectiveness in Hong Kong self-managing schools. Questionnaire survey data from teachers in schools participating in the Phases 1 and 2 of the School Management Initiative scheme in Hong Kong, are analysed. Principal's support and resource support are found to be significant factors in predicting positive outcomes of planning. The concept of flexible planning is explored and conceptualized in terms of built-in flexibility and flexibility through evaluation. An interactive model, `A Self-Managing School Planning Model', which is responsive, recurrent and flexible in nature is proposed.

Suggests that a desire on the part of teachers to be more involved in the corporate affairs of the school may stem from a lack of trust in the decision makers and the decision‐making processes. To assist those involved in the management of schools, presents a theoretical framework for research and a financial decision‐making model, based on the establishment of a management philosophy built on trust. Demonstrates how this model helps to differentiate management and classroom or technical decisional issues. Identifies the roles and responsibilities of those involved in the processes. Outlines procedures for effective financial decision making at the school site.

The dynamic behavior of powdered materials such as granular silica (sand), technical ceramics, and porous geological substances has importance to a variety of engineering applications. Structural seismic coupling, planetary science, earth penetration mechanics, and the performance of ceramic armors are just some of application areas. Although the mechanical behaviors of sand and other granular ceramics have been studied extensively for several decades, the dynamic behavior over a range of strain rates and pressures of such materials remains poorly understood. This paper describes how instrumented electromagnetic tube compression driven by capacitive discharge can be used to measure compaction of porous materials at moderate pressures and controlled strain rates. The technique relies on electromagnetically crushing a powder-filled conductive tube. By measuring the current as a function of time and the tube displacement through Photon Doppler Velocimetry (PDV) sufficient data can be obtained to reveal the behavior of the porous material. The method will be described in detail and example data will be shown for compaction of silica sand.

Electrohydraulic (submerged arc discharge) forming of sheet metal parts has been used as a specialized high speed forming method since the 1960 s. The parts formed generally had a major dimension in the 5 to 25 cm range and required gross metal expansion in the centimeter range. In the descriptions of this process found in the literature, the pressure front emanating from the initial plasma generated by the arc is considered to be uniformly spherical in nature. At least one commercial system used this model to design hardware for pressure front focusing to optimize the forming process[1] and it has been the subject of continued research [2]. Recently, there has been commercial interest in adopting the electro-hydraulic method for the production of much smaller parts requiring very high die contact pressures but little gross sheet expansion. The forming of these small shallow parts required only a few kilojoules but proved to be problematic in other terms. The process development clearly showed indications of random patterns of large pressure heterogeneity across distances in the millimeter range. The apparent pressure heterogeneity produced unacceptable small scale variation in the part geometry. A test program was designed to verify and quantify this effect using a target (die) consisting of a flat plate having small closely spaced holes. This 50 mm diameter target proved very effective in clearly showing the extent of the heterogeneity as well as the approximate local pressures. Various discharge energies were investigated along with different chamber shapes and pressure transfer mediums. The pressure heterogeneity across the target face was a common feature to all experiments. These test results indicate that a uniform pressure front model can be seriously in error for the electrohydraulic process as implemented to date. The results of a qualitative hydro-code model of the test system including the discharge event are presented. The model results are similar enough to the experimental to imply that the coaxial electrode s inherent off center discharge is a primary suspect among potential explanations for the observed heterogeneity in terms of asymmetric shock interaction. The absence of this phenomena in the earlier electrohydraulic forming literature is also discussed.

Modeling electromagnetic forming processes is in many ways simpler than modeling traditional metal forming processes. In electromagnetic forming the problem is often dominated by inertial acceleration by a magnetic field. This is a much better posed problem than the more traditional ones that are often dominated by complex three dimensional constitutive behavior and frictional effects. However, important aspects of the problem are dominated by the constitutive properties of the material, and often electromagnetic forming is performed in a regime where there is little reliable material strength data. Strain rates are often high (102 to 104 s-1 is the typical range for electromagnetic forming). Also, heat is generated both by ohmic heating as well as by plastic deformation, and peak temperatures can be quite high. Also, while hightemperature, high-strain-rate data is scarce, there is little or no data in cases where temperature rises significantly over very short times (tens of micro-seconds) as happens in electromagnetic metal forming. This rapid temperature rise is very important to the material response because the short time scales largely preclude the material from recovery and recrystallization processes and precipitates cannot dissolve as they normally would in an age-hardening alloy in these time scales. This presentation will show how advanced instrumentation, particularly the Photon Doppler Velocimeter (PDV) can be coupled with electromagnetic forming and provide both avenues to characterize material as well as to provide very critical tests of numerical models of the process.

Sea ice is the dominant feature of polar oceans and contains significant quantities of microalgae. When sea ice forms and melts, the microalgal cells within the ice matrix are exposed to altered salinity and irradiance conditions, and subsequently, their photosynthetic apparatuses become stressed. To simulate the effect of ice formation and melting, samples of sea-ice algae from Cape Hallett (Antarctica) were exposed to altered salinity conditions and incubated under different levels of irradiance. The physiological condition of their photosynthetic apparatuses was monitored using fast and slow fluorescence-induction kinetics. Sea-ice algae exhibited the least photosynthetic stress when maintained in 35‰ and 51‰ salinity, whereas 16, 21, and 65‰ treatments resulted in significant photosynthetic stress. The greatest photosynthetic impact appeared on PSII, resulting in substantial closure of PSII reaction centers when exposed to extreme salinity treatments. Salinity stress to sea-ice algae was light dependent, such that incubated samples only suffered photosynthetic damage when irradiance was applied. Analysis of fast-induction curves showed reductions in J, I, and P transients (or steps) associated with combined salinity and irradiance stress. This stress manifests itself in the limited capacity for the reduction of the primary electron receptor, QA, and the plastoquinone pool, which ultimately inhibited effective quantum yield of PSII and electron transport rate. These results suggest that sea-ice algae undergo greater photosynthetic stress during the process of melting into the hyposaline meltwater lens at the ice edge during summer than do microalgae cells during their incorporation into the ice matrix during the process of freezing. © 2007 Phycological Society of America.

Retaining wall design has long been carried out with the aid of either the Rankine or Coulomb theories of earth pressure. To obtain a closed-form solution, these traditional earth pressure theories assume that the soil is uniform. The fact that soils are actually spatially variable leads, however, to two potential problems in design: do sampled soil properties adequately reflect the effective properties of the entire retained soil mass, and does spatial variability of soil properties lead to active earth pressure effects that are significantly different from those predicted using traditional models? This paper combines non-linear finite element analysis with random field simulation to investigate these two questions and assess just how safe current design practice is. The specific case investigated is a two-dimensional frictionless wall retaining a cohesionless drained backfill. The wall is designed against sliding using Rankine's earth pressure theory. The design friction angle and unit weight values are obtained by sampling the simulated random soil field at one location, and these sampled soil properties are then used as the effective soil properties in the Rankine model. Failure is defined as occurring when the Rankine predicted force acting on the retaining wall, modified by an appropriate factor of safety, is less than that computed by the random finite element method employing the actual soil property (random) fields. Using Monte Carlo simulation, the probability of failure of the traditional design approach is assessed as a function of the factor of safety used and the spatial variability of the soil.

It is widely appreciated that, in civil engineering and building projects, the largest element of financial and technical risk usually lies in the ground. Almost exclusively, the scope of geotechnical investigations is governed not by what is needed to characterise the subsurface conditions appropriately but, rather, by how much the client and project manager are willing to spend. There is often little correlation between the variability of the ground and the scope of the investigation. This paper presents the results of a Monte Carlo simulation incorporating many 3D single-layer soil profiles with different statistical characteristics. A three-storey building founded on nine pad footings is used to assess the reliability of various site investigation scopes and test methods. The pad footings are designed on the basis of settlement, and are examined using 3D finite element analysis and Schmertmann's method. It is observed, as expected, that the likelihood of underdesigning or overdesigning a footing decreases as the scope of the investigation increases. The relationship between these likelihoods and the variability of the ground is presented.