Using fractal geometry to make rapid field measurements of riverbed topography at ecologically useful spatial scales

A method is described for making rapid in situ field measurements of riverbed topography over spatial scales of ≅1–10 m. This method uses rolling balls to make quick, accurate measurements of river-bed roughness at several spatial scales. Random sampling and replication generate multiple estimates of the fractal dimension (d) that can be used to test for significant differences in the complexity of riverbed architecture between habitat types and spatial scales.

Faster, richer, better: rapid appraisal techniques for the study of IS implementation in virtual communities

A major issue in Information Systems (IS) research is how to combine relevance and rigor (Benbasat and Zmud, 1999) and reduce the widening gap between research results and adoption (Dunn, 1994). Qualitative researchers make use of interpretivist methods to add richness and depth to their understanding of user problems. Interpretivist methods applied to IS implementations can thus result in research which communicates those findings more effectively. However standard interpretivist data-collection and analysis methods can be time-consuming and expensive. Findings based on these methods may be irrelevant to practitioners by the time they reach publication stage. A potential solution to this problem lies in Rapid Appraisal or RA, a qualitative appraisal methodology derived from rural development-related research. It offers IS researchers an additional technique for learning and acquiring relevant information in a limited period of time that  supplements current data collection and analysis techniques. RA adds value to the traditional approach for studying diffusion of innovation, supporting and extending the IS researcher’s qualitative ‘tool-kit’. In this paper we review an electronic gateway designed to facilitate the diffusion of an Australian government to business [G2B] export documentation system, EXDOC, which was first implemented with meat producers. RA techniques were used to collect and analyse data regarding the implementation of the first regional Electronic Trade Facilitation Center [ETFC] successfully established for Australian exporters in the horticulture sector. The findings from the original EXDOC implementation in the meat sector were confirmed and extended through this study. These include the importance of developing a governance structure that ensures all community members share the benefits of an implementation and the fact that virtual trading communities are attractive to users only if they add value to their business and extend standard ways of operating. Interactive interviews, part of the RA approach; also enabled us to expand our understanding of the way in which procedures developed in the course of implementing an electronic market represent value-adding opportunities for virtual trading communities. The paper has special relevance for researchers investigating adoption and diffusion issues experienced by small-scale producers with low exposure to technology in remote and rural settings.

Rapid determination of carbohydrates in heroin drug seizures using capillary electrophoresis with short-end injection

A simple and rapid method for the analysis of carbohydrates in heroin samples by capillary electrophoresis utilizing a borate complexation method is described. Separations were performed using an uncoated fused silica capillary, 50 cm × 50 mm I.D. × 360 mm O.D. with an effective separation length of 9 cm. The system was run at 60°C with an applied voltage of -8 kilovolts. Injection of each sample was for 1 sec at -50 mbar. UV detection was employed with the wavelength set at 195 nm. The background electrolyte consisted of 65 mM borate, pH 12.0. Samples and standards were prepared in the run buffer containing 2 mg/mL of mannose as an internal standard. Under these conditions a test mixture containing glucose, sucrose, lactose, mannitol and mannose as an internal standard was resolved within 5 min. The method was used to determine the concentration of carbohydrates in heroin seizure samples and synthetic heroin samples. The results were in good agreement with the reported values.

The rapid analysis of heroin drug seizures using micellar electrokinetic chromatography with short-end injection

A simple and rapid method for the analysis of heroin seizures by micellar electrokinetic chromatography with short-end injection is described. Separations were performed using an uncoated fused silica capillary, 50 cm×50 mm I.D.×360 mm O.D. with an effective separation length of 8 cm. The system was run at 25°C with an applied negative voltage of –25 kilovolts. Injection of each sample was for 2 s at –50 mbar. UV detection was employed with the wavelength set at 210 nm. The background electrolyte consisted of 85:15 (water:acetonitrile, v/v) containing final concentrations of 25 mM SDS and 15 mM sodium borate, pH 9.5. Samples and standards were prepared in 0.1% v/v acetic acid and diluted in the run buffer containing 1 mg/ml of N,N-dimethyl-5-methoxytryptamine as an internal standard. Under these conditions a text mixture containing caffeine, paracetamol, morphine, codeine, heroin, and acetylcodeine was resolved within 1.5 min. The method was used to determine the concentration of heroin in heroin seizure samples, and the results were in good agreement with those obtained by a validated gas chromatographic method.

A rapid test for heroin (3,6-Diacetylmorphine) based on two chemiluminescence reactions

A rapid method for screening drug seizure samples for 3,6-diacetylmorphine (heroin), which consists of a simple hydrolysis procedure and flow-injection analysis with two chemiluminescence reagents, is described. Before hydrolysis, 3,6-diacetylmorphine evokes an intense response with a tris(2,2'-bipyridyl)ruthenium(III) reagent (prepared by dissolving the perchlorate salt in acetonitrile), and a relatively weak chemiluminescence response with a second reagent: potassium permanganate in an aqueous acidic polyphosphate solution. However, the permanganate reagent is extremely sensitive toward the hydrolysis products of 3,6-diacetylmorphine (i.e., 6-monoacetylmorphine and morphine). Some compounds commonly found in drug laboratories may cause false positives with tris(2,2'-bipyridyl)ruthenium(III), but do not produce the markedly increased response with the permanganate reagent after the hydrolysis procedure. The combination of these two tests therefore provides an effective presumptive test for the presence of 3,6-diacetylmorphine, which we have verified with 14 samples obtained from a forensic science laboratory.

Rapid composite tube manufacture utilizing the quickstep™ process

In this study, a novel method for manufacturing composite tubes utilizing the Quickstep^TM process has been developed. Tubes manufactured from `quick-cure' Toray G83C prepreg have demonstrated highly repeatable axial crush behavior with an average specific energy absorption (SEA) of 86 kJ/kg. The cure cycle is optimized by comparing the results from compression, dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC), and porosity testing. The tube lay-up is optimized using compression and porosity test results. The effect of changes in fiber-orientation on SEA is also investigated. Process development has resulted in a robust manufacturing method capable of producing fully cured, high performance composite tubes with a cure cycle of 7 min. This corresponds to a 95% reduction in time compared to an equivalent autoclave cycle.

Robust control applied to metal spraying for rapid tooling

The spray forming process is a novel method of rapidly manufacturing tools and dies for stamping and injection operations. The process sprays molten tool steel from a set of arc spray guns onto a ceramic former to build up a thick steel shell. The volumetric contraction that occurs as the steel cools is offset by a volumetric expansion taking place within the sprayed steel, which allows the dimensional accurate tools to be produced. To ensure that the required phase transformation takes place, the temperature of the steel is regulated during spraying. The sprayed metal acts both as a source of mass and a source of heat and by adjusting the rate at which metal is sprayed; the surface temperature profile over the surface of the steel can be controlled. The temperature profile is measured using a thermal imaging camera and regulated by adjusting the rate at which the guns spray the steel. Because the temperature is regulated by adjusting the feed rate to an actuator that is moving over the surface, this is an example of mobile control, which is a class of distributed parameter control. The dynamic system has been controlled using a PI controller before. The paper describes the application of H∞ tracking type controller as the desire was for the average temperature to follow a desired profile. A study on the controllability of the underlying system was aimed at.

Rapid determination of papaver somniferum alkaloids in process streams using monolithic column high-performance liquid chromatography with chemiluminescence detection

We have combined high-performance liquid chromatography (HPLC) separations using a monolithic column with acidic potassium permanganate and tris(2,2′-bipyridyl)ruthenium(II) chemiluminescence detection in a rapid and highly sensitive method to monitor the process of extracting opiate alkaloids from Papaver somniferum. Due to the high flow rates allowed with the monolithic column and the inherent selectivity of the chemiluminescence reactions, the four predominant alkaloids – morphine, codeine, oripavine and thebaine – were determined in less than 2 min. The results obtained with numerous process samples compared favourable with those of the standard HPLC methodology. Limits of detection were 1 × 10⁻¹⁰ M, 5 × 10⁻¹⁰ M, 5 × 10⁻¹⁰ M and 1 × 10⁻⁹ M, for morphine, codeine, oripavine and thebaine, respectively.

A rapid cell counting method utilising acridine orange as a novel discriminating marker for both cultured astrocytes and microglia

Cell culture analyses of growth, morphology and apoptosis commonly require counting of different cell types stained with antibodies to discriminate between them. Previously, we reported the use of l-Leucine methyl ester (l-LME) to prepare purified cultures of type 1 astrocytes with minimal microglia, and staining by GFAP and CD antibodies, respectively. Here, we demonstrate a novel use of acridine orange (AO) for rapid discrimination between these cell types using fluorescence microscopy. AO accumulates in the lysosomes and also binds strongly to nuclear DNA and cytoplasmic/nucleolar RNA. Microglia may contain abundant lysosomes due to known roles in homeostasis and immune response. AO staining of lysosomes was tested at a range of concentrations, and 2.5 μg/mL was most suitable. In agreement with previous reports, microglia treated with AO showed very intense yellow, orange or red granular cytoplasmic staining of lysosomes. Microglia contain a substantially higher number of lysosomes than astrocytes, which have a variable amount. We measured the microglia population at 5.14 ± 0.50% in mixed cultures. Thus, these results show AO is a novel discriminatory marker, as microglia were easily observed and counted in clumps on top of the monolayer of astrocytes, providing a rapid alternative to time-consuming and costly antibody-based assays.

A flow control methodology for the rapid generation of vehicle traffic models

This paper presents a conveyor-based methodology to model complex vehicle flows common to factory and distribution warehouse facilities. The AGV and human path modelling techniques available in many commercial discrete event simulation packages require extensive knowledge and time to implement even the simplest flow control rules for multiple vehicle interaction. Although discrete event simulation is accepted as an effective tool to model vehicle delivery movements, human paths and delivery schedules for modern assembly lines, the time to generate accurate models is a significant limitation of existing simulation-based optimisation methodologies. The flow control method has been successfully implemented using two commercial simulation packages. It provides a realistic visual representation, as well as accurate statistical results, and reduces the model development process cost.

A sensitive procedure for the rapid determination of arsenic(III) by flow injection analysis and chemiluminescence detection

A novel chemiluminescence flow injection procedure for the determination of As(III) in aqueous samples is described. The method involves injection of As(III) samples into a 1% (m/v) sodium hexametaphosphate in 0.02 M H₂SO₄ carrier stream, which then merges at a Y-piece with a reagent stream consisting of potassium permanganate (5.0 × 10⁻⁵ M) made up in the acidic sodium hexametaphosphate carrier solution. The chemiluminescence intensity of the resulting reaction mixture was measured at a photomultiplier tube operated at a voltage of 0.93 kV. Under optimized conditions, the method is characterised by a linear range from 0.5 to 5.0 μg l⁻¹, a detection limit of 0.3 μg l⁻¹ and a sampling frequency of 150 h⁻¹. The effects of common anionic and cationic interferences were investigated, and it was found that the only ions to cause serious interference were those which react with potassium permanganate, namely sulphide, iodide and ferrous.

On rapid vector alignment in permanent magnet brushless motor

A software replacement for the commutation signals of a permanent magnet brushless motor is presented. The feedback observed acceleration loop or equivalently the high-order position polynomial controller allows finding the initial relative orientation between the two magnetic fields of the motors within a fraction of a second. Also, using the proposed method allows a considerable cost saving, since the transducer that is usually used for this purpose can be eliminated. The cost saving is most obvious in the case of linear motors and angle motors with large diameters. The way the problem is posed is an essential part of this work and it is the reason behind the apparent simplicity of the solution. The method has been tested when a relative encoder was used and the motor current was regulated.