A comparative study of some computer algebra packages which determine the lie point symmetries of differential equations

The study seeks to determine which of five computer algebra packages is best at finding the Lie point symmetries of systems of partial differential equations with minimal user intervention. The chosen packages are LIEPDE and DIMSYM for REDUCE, LIE and BIGLIE for MUMATH, DESOLV for MAPLE, and MATHLIE for MATHEMATICA. A series of systems of partial differential equations are used in the study. The paper concludes that while all of the computer packages are useful, DESOLV appears to be the most successful system at determining the complete set of Lie point symmetries of systems of partial differential equations.

A comparative study on preparation of TiO2 pellets as photocatalysts based on different precursors

The porous Ti0₂ pellets were prepared based on pigment grade titaina, P25 titania powder and titaniurn(lV) butoxide. The characterization was done with X-Ray diffraction, scanning electron microscopy and BET measurements. The result shows that Ti0₂ pellets by using titaniurn(IV) butoxide with some addictive have the best surface porosity, with specific surface area of 196.9m²/g. For pigment grade titania and P25 titania powder, it is still effective to enhance the surface area after reassembling. The surface area increased from 11.6 to 29.2 m²/g for pigment grade titania and from 50 to 84.4 m²/g for P25 titania powder. Furthermore, it has been investigated on how to optimize and get the highest surface area by controlling the sintering temperature, reaction temperature, pH of solution, and the amount of alcohol and addictive of surfactant during preparation. The experimental photocatalytic degradation of acetone and toluene was performed using titania pellets made from P25 titania powder.

A comparative study at the logical level of centralised and distributed recovery in clusters

Cluster systems are becoming more prevalent in today’s computer society and users are beginning to request that these systems be reliable. Currently, most clusters have been designed to provide high performance at the cost of providing little to no reliability. To combat this, this report looks at how a recovery facility, based on either a centralised or distributed approach could be implemented into a cluster that is supported by a check pointing facility. This recovery facility can then recover failed user processes by using checkpoints of the processes that have been taken during failure free execution.

A comparative study of construction industry size and structure between the UK and Australia and the significance of industry fragmentation

While comparing both the size and structure between the UK and Australian construction industries, this study reveals that the UK construction industry is about two and a half times larger than the Australian construction industry, and both industries are dominated by the proportion of small firms. The issue of fragmentation is characteristic of the construction industries in these two countries, and beyond. This study then develops a self recruiting-subletting cost indifference point model to explain why fragmentation occurs. Although the high proportion of small firms in the construction industry has been criticised as it prevents the exploitation of economies of scale, the self recruiting-subletting cost indifference point model theoretically proposes that subletting is usually profitable for construction firms. Thus the size distribution of the construction industry has a propensity to skew towards small firms.

Online and postal data collection methods: a comparative study

Computer-mediated marketing research has been enthusiastically embraced by marketing organisations and those servicing them, for many reasons. While researchers using the Internet (Net) and World Wide Web (Web) in its early years reported benefits such as high response levels, there are now issues in this regard. This paper reports on the outcomes of a probabilistic study involving football club members (subscribers) involving both postal and online (e-mail invitation and HTML Web form) data collection methods. The paper reports differences in both the response pattern and demographic profile of respondents between the groups such as to warrant further examination of the methods used in online marketing research, and to suggest the need for further study.

A comparative study on economic factors of construction industries in Australia and China

The construction sector produces the facilities needed for a large majority of the production of goods and services, in which a sizeable proportion of Gross Domestic Product is generated. Recent trends in the globalisation of construction markets indicate that many countries consider construction industry competitiveness as crucial, and are working to increase construction productivity, in particular where the construction industries play an important role in their economic development. This paper first points out the research importance in international construction. Based on economic analyses of construction industries, a study is then carried out to focus on the economic sizes and benefits of the Chinese construction industry and to compare them with the Australian construction industry. Results derived from such an international construction comparison will assist in the Australian construction communities understanding the construction markets and industries in China and will benefit in international construction participation and cooperation.

A comparative study of computational value in visual cues used in positioning 3D objects

This paper explores the comparative computational values of using a variety of visual cues in 3D environments. The authors reflect upon the possible repercussions of computationally less expensive visual cues on users' ability to efficiently and accurately interact with three-dimensional images. This study compares the effectiveness of expensive soft shadows against less expensive hard shadows and expensive partial-occlusion (obtained by semi-transparent surface) against less expensive occlusion on users' ability to accurately position objects in imminent contact with other objects in a three-dimensional environment.

A comparative study of the contents of corporate codes of ethics in Australia, Canada and Sweden

This paper reports on and analyzes the contents of 197 corporate codes of ethics (78 Australian, 80 Canadian and 39 Swedish). Among other things, it was found that the contents of the Australian and Canadian codes were similar, reflecting the similar histories and cultures (as measured by Hofstede's dimensions) of these two countries. Further, the contents of the Swedish codes were found to be very different from the Australian and Canadian codes in some areas, reflecting the cultural differences between Sweden and the other two countries.

The questioning skills of clinical teachers and preceptors: a comparative study

Aim of the study. The purpose of this study, conducted as partial requirement for a Master of Nursing Studies Degree, was to explore, describe and compare the level of questions asked by clinical teachers and preceptors.

Background. Questioning is one of many teaching/learning strategies thought to facilitate the development of critical thinking skills which are integral to nursing practice. As such the type and number of questions asked have implications for student learning. Currently in Melbourne, Australia, many undergraduate nursing degree courses utilize both clinical teachers and preceptors to facilitate student learning in the clinical setting.

Design. A comparative descriptive design was used. Participants were given three acute care patient scenarios involving an undergraduate nursing student, as part of a questionnaire, and asked to identify the questions they would ask the student in relation to the scenario.

Findings. Data revealed that the clinical teachers had considerably more years of experience in their role and higher academic qualifications than did the preceptors. The clinical teachers also asked a greater number of questions overall and more from the higher cognitive level. Despite this, the findings suggest that both clinical teachers and especially preceptors need to increase the number of higher level questions they ask.

Conclusions. Based on the findings of this study, it is evident that there is a need for further comparative studies into the questioning skills of clinical teachers and preceptors. Also, these two groups require education about the importance of higher level questioning for student learning as well as how to ask questions generally.

Comparative study on thermodynamical and electrochemical behavior of Al88Ni6La6 and Al86Ni6La6Cu2 amorphous alloys

Two amorphous ribbons with the compositions of Al₈₈Ni₆La₆ and Al₈₆Ni₆La₆Cu₂ were made using the meltspun method, and their thermal response and electrochemical behavior were studied comparatively. Differential scanning calorimetry (DSC) and electrochemical polarization measurements indicated that Al₈₆Ni₆La₆Cu₂ exhibited slightly higher crystallization temperature (T_x), lower melting point (T₁) and better corrosion resistance in 0.01 mol · L⁻¹ NaCl alkaline solution. These results demonstrated that Cu (2%) addition could slightly promote the glass forming ability, but it could greatly improve the corrosion resistance of Al₈₈Ni₆La₆ alloy in 0.01 mol · L⁻¹ NaCl alkaline solution.

A comparative study on the felting propensity of animal fibers

The felting propensity of different animal fibers, particularly alpaca and wool, has been examined. The Aachen felting test method was employed. 1 g of each type of fiber was soaked in 50 ml of wetting solution and agitated in a dyeing machine to make felt balls. The diameter of each ball was measured in nine directions and the ball density was calculated in g/cm3; the higher the density value of the ball, the higher the feltability of the fibers. The effects of fiber diameter and fiber length on the felting propensity of these fibers were investigated. The results show that the alpaca fibers felt to a higher degree than wool fibers, and short and fine cashmere fibers have lower felting propensity than wool fibers at a similar diameter range. There is a higher tendency of felting for bleached and dyed alpaca fibers than for untreated fibers. Fiber length has a remarkable influence on the propensity of fiber felting. Cotton and nylon fibers were also tested for felting propensity to verify the mechanism responsible for the different fiber felting behavior.

A comparative study of microstructures and mechanical properties obtained by bar and plate rolling

Microstructures and mechanical properties of a low carbon steel were studied after plate rolling and bar rolling. Plate rolling is characterized as a monotonic compressive loading, while bar rolling is characterized as a cross-compressive loading. A four-pass plate rolling and bar rolling experiment was designed so that the material experiences the same amount of strain at each pass during rolling. The rolling experiment was performed at moderately high temperatures (450, 550 and 650 °C). The microstructures and mechanical properties of the low carbon steel acquired from the two types of rolling experiments were compared. The results revealed that differences of loading path attributed by monotonic loading (plate rolling) and cross loading (bar rolling) significantly influenced the microstructures and mechanical properties such as yield stress, ultimate tensile stress, strain hardening exponent and elongation of the low carbon steel.