E-commerce and graduate education: is educational quality taking a nose dive?

Purpose: Online education has been growing rapidly, but has not had the benefit of the extensive teaching pedagogy development of traditional face-to-face teaching. This paper aims to provide a review of the current literature and present the results of a survey, conducted to determine the effectiveness of a graduate online subject. Design/methodology/approach: The literature was reviewed to identify measures of success and quality in online education delivery. These measures were then considered in relation to their application in practice via a case study based around a survey conducted at Deakin University in Australia. Findings: A total of 16 relevant measures of teaching quality were identified in the literature. Most measures had elements of bias and some were more generally applicable to online learning. The case study suggested that the value of computer mediated learning in an online environment was limited and that a combination of print and computer mediated conferencing performed better in more of the identified quality matrices. Practice implications: Online learning does not save teaching resources if standards of quality are maintained. It can be used to provide a remote teaching facility, provided it is backed up by resources such as printed study guides. For the subject evaluated, online mediated learning did not the provide the same quality of education. Originality/value: Whilst some research has been conducted in this area, no substantive grounded theory has been applied to postgraduate or fee-paying online education regimes. As a result, case studies of such applications can be very helpful in the design of future teaching systems.

The nose and tongue as chemical detectors

Human chemical senses are the gatekeepers of our digestive system. Chemical separation combined with human sensory perception has been used to isolate and identify a natural non-steroidal anti-inflammatory compound in olive oil.

Laboratory model studies of flushing of trapped salt water from a blocked tidal estuary

Results are presented from a series of laboratory model studies of the flushing of saline water from a partially- or fully-closed estuary. Experiments have been carried out to determine quantitatively the response of the trapped saline volume to fresh water flushing discharges Q for different values of the estuary bed slope α and the density difference (∆ρ)_o between the saline and fresh water. The trapped saline water forms a wedge within the estuary and for maintained steady discharges, flow visualisation and density profile data confirm that its response to the imposition of the freshwater purging flow occurs in two stages, namely (i) an initial phase characterised by intense shear-induced mixing at the nose of the wedge and (ii) a relatively quiescent second phase where the mixing is significantly reduced and the wedge is forced relatively slowly down and along the bed slope. Scalings based upon simple energy balance considerations are shown to be successful in (i) describing the time-dependent wedge behaviour and (ii) quantifying the proportion of input kinetic energy converted into increasing the potential energy of the wedge/river system. Measurements show that the asymptotic value of the energy conversion factor increases with increasing value of the river Froude number Fr_o at small values of Fr_o, thereafter reaching a maximum value and a gradual decrease at the highest values of Fr_o. Dimensional analysis considerations indicate that the normalised, time-dependent wedge position (x_w)³(g')o/q² can be represented empirically by a power-law relationship of the form (x_w)[(g')_o/q²]^1/3 =C [(t)[(g')_o²/q]^1/3]"where the proportionality coefficient C is a function of both Fr_o and the slope angle α and the exponent n has a value of 0.24. Successful attempts are made to relate the model data to existing field observations from a microtidal estuary.

Experiments with multiple, intermittent periodic flushing flows confirm the importance of the starting phase of each flushing event for the time dependent behaviour of the saline wedge after reaching equilibrium in the intervals between such events. For the parameter ranges investigated and for otherwise-identical external conditions, no significant differences are found in the position of the wedge between cases of sequential multiple flushing flows and steady single discharges of the same total duration.

The salt wedge position in a bar-blocked estuary subject to pulsed inflows

A series of laboratory experiments were carried out to investigate the response of a bar-blocked, saltwedge estuary to the imposition of both steady freshwater inflows and transient inflows that simulate storm events in the catchment area or the regular water releases from upstream reservoirs. The trapped salt water forms a wedge within the estuary, which migrates downstream under the influence of the freshwater inflow. The experiments show that the wedge migration occurs in two stages, namely (i) an initial phase characterized by intense shear-induced mixing at the nose of the wedge, followed by (ii) a relatively quiescent phase with significantly reduced mixing in which the wedge migrates more slowly downstream.

Provided that the transition time t_T between these two regimes satisfies t_T>g′h⁴L/q³α, as was the case for all our experiments and is likely to be the case for most estuaries, then the transition occurs at time t_T=1.2(gα³L⁶/g′³q²)^1/6, where g′=gΔρ/ρ0 is the reduced gravity, g the acceleration due to gravity, Δρ the density excess of the saline water over the density ρ₀ of the freshwater, q the river inflow rate per unit width, and L and α are the length and bottom slope of the estuary, respectively.

A simple model, based on conversion of the kinetic energy of the freshwater inflow into potential energy to mix the salt layer, was developed to predict the displacement xw over time t of the saltwedge nose from its initial position. For continuous inflows subject to t<t_T, the model predicts the saltwedge displacement as x_w/h=1.1 (t/τ)^1/3, where the normalizing length and time scales are h=(q²/g)^1/3 and τ=g′α²h4L/q³, respectively. For continuous inflows subject to t>tT, the model predicts the displacement as xw/h=0.45N1/6(t/τ)1/6/α, where N=q²/g′h²L is a non-dimensional number for the problem. This model shows very good agreement with the experiments. For repeated, pulsed discharges subject to t<t_T, the saltwedge displacement is given by (xw/h)3−(x0/h)(xw/h)2=1.3t/τ, where x₀ is the initial displacement following one discharge event but prior to the next event. For pulsed discharges subject to t>t_T, the displacement is given by (xw/h)⁶−(x0/h)(xw/h)⁵=0.008N(t/τ)/α⁶. This model shows very good agreement with the experiments for the initial discharge event but does systematically underestimate the wedge position for the subsequent pulses. However, the positional error is less than 15%.

Audit of the use of antimicrobial prophylaxis in nasal surgery at a speciali

Background: In 2002−03 a retrospective audit of the use of surgical antimicrobial prophylaxis (AMP) for elective nasal surgery was undertaken at the Royal Victorian Eye and Ear Hospital (RVEEH). The RVEEH is a publicly funded teaching hospital that provides specialist eye, nose and throat medicine in Victoria, Australia. The aim of the audit was to determine the extent to which the use of antimicrobial prophylaxis in the hospital was consistent with Australian and international evidence-based guidelines and if there was a need for the hospital to develop internal guidelines for the use of AMP.

Methods: The histories of 500 consecutive patients who had undergone nasal surgery within the study period of August 2001 and July 2002 were examined. The data collected from these histories included information such as the patients' age, gender, diagnosis, surgical procedure performed, antimicrobial agents used, and the length of follow up and a range of factors shown in previous studies to increase the risk of surgical site infection.

Results: A total of 306 (72.86%) patients were found to have received antimicrobial agents either prior to admission, during admission or on discharge. Only 24 patients (5.71%) were administered antimicrobials immediately prior to surgery and at no other time.

Conclusions: The findings of this study support the need for further research to examine the appropriateness of the use of AMP at the RVEEH and the need for internal guidelines for its use.

The cost of community-managed viral respiratory illnesses in a cohort of healthy preschool-aged children

Background : Acute respiratory illnesses (ARIs) during childhood are often caused by respiratory viruses, result in significant morbidity, and have associated costs for families and society. Despite their ubiquity, there is a lack of interdisciplinary epidemiologic and economic research that has collected primary impact data, particularly associated with indirect costs, from families during ARIs in children.
Methods : We conducted a 12-month cohort study in 234 preschool children with impact diary recording and PCR testing of nose-throat swabs for viruses during an ARI. We used applied values to estimate a virus-specific mean cost of ARIs.
Results : Impact diaries were available for 72% (523/725) of community-managed illnesses between January 2003 and January 2004. The mean cost of ARIs was AU$309 (95% confidence interval $263 to $354). Influenza illnesses had a mean cost of $904, compared with RSV, $304, the next most expensive single-virus illness, although confidence intervals overlapped. Mean carer time away from usual activity per day was two hours for influenza ARIs and between 30 and 45 minutes for all other ARI categories.
Conclusion : From a societal perspective, community-managed ARIs are a significant cost burden on families and society. The point estimate of the mean cost of community-managed influenza illnesses in healthy preschool aged children is three times greater than those illnesses caused by RSV and other respiratory viruses. Indirect costs, particularly carer time away from usual activity, are the key cost drivers for ARIs in children. The use of parent-collected specimens may enhance ARI surveillance and reduce any potential Hawthorne effect caused by compliance with study procedures. These findings reinforce the need for further integrated epidemiologic and economic research of ARIs in children to allow for comprehensive cost-effectiveness assessments of preventive and therapeutic options.

Evaluation of the thermal behaviour of bevelled cutting inserts using a numerical approach

The nose geometry of a hard and brittle metal cutting tool is generally modified in order to avoid the premature failure due to fracture under tensile stresses. While most research findings point to a favourable mechanical load pattern, the possible influence of the shape of the geometry on the thermal fields and the consequent changes in the stressed state of the tool seem to have attained less attention. The present work aims at establishing the thermal behaviour of bevelled tools under varying geometrical and process parameters. Data generated from statistically designed experiments and quick-stop chip samples are coupled to conduct numerical investigations using a mixed finite and boundary element solution to obtain the temperature distribution in bevelled carbide inserts. Due consideration is given to the presence of the stagnation zone and its size and shape. While the cutting forces and temperatures increased owing to the blunt shape of the tool, the possible absence of tensile stresses was found to be the likely effect of a more uniform temperature distribution resulting from a significant plastic contact on the principal flank and the consequent flank heat source. The characteristic low-temperature zones close to the nose of the conventional tool are taken over by the stagnation zone in bevelled tools. © IMechE 2007.

Machinability assessment of multi component high entropy alloys

Due to high demand in engineering materials especially with high strength to weight ratio and advantageous material properties such as wear resistance and thermal stability or high entropy. This essential parametric enhancement has led to the development of Multi Component High Entropy Alloys (MCHEA). It has been proposed in this study to investigate the machinability characteristics of MCHEA. The MCHEA are usually amalgamation with multiple elements such as aluminium, cobalt, manganese, nickel, chromium and titanium with their individual concentrations ranging from 5-35% overall. The experimental design consists of basic characterization of the material and conducting machinability trails-milling. The basic material characterization consists of evaluating bulk hardness, microstructural image generation, microhardness and chemical composition using spectrometry. The milling trails are conducted using 2 flute, 30º helix ball nose solid carbide end-mill cutting tool with combination of cutting parameters such as constant cutting speed, 30 m/min; varied feed, 0.01 mm/tooth and 0.02mm/tooth; depth of cuts, 1.5 and 3 mm and coolant on. The outputs obtained from the machining trails are subjected to analysis such as cutting force. In addition, the surface roughness of the material is evaluated using 3D optical surface profilometer. Similarly, the solutions to alleviate the drawbacks are also exemplified during machining of MCHEA.