Showing papers by "Griffith University published in 1994"

Purification of C60 and C70 by selective complexation with calixarenes

Abstract: MOLECULAR complexation of fullerenes in host–guest complexes has the potential to afford efficient large-scale purification of fullerenes1. This method would avoid the losses inherent in the chromatographic techniques currently in use, which arise from irreversible absorption on the stationary phase2. Several host-guest interactions have been reported for C60, including the formation of complexes with 1,4-hydroquinone3,4, azacrown compounds5, certain water-soluble macrocycles such as γ-cyclodextrin6–8, and complexation between C60 and an iridium phosphine in which pendant groups attached to a phosphorus atom form a cradle for an adjacent C60 molecule9. Other relevant studies are the inclusion of C60 into a microporous aluminophosphate10 and the formation of a charge-transfer complex between C60 and a thiafulvalene11. Here we show that both C60 and C70 will form discrete complexes with calixarenes, bowl-shaped macrocycles with hydrophobic cavities. Complexation of p-Bu'-calix[8]arene with a mixture of the toluene extract of 'crude' fullerene soot, followed by a series of recrystallizations, affords >99.5% pure C6. Our approach could lead to a substantial reduction in the cost of purifying C60 and C70.

The usefulness of management accounting systems, functional differentiation and managerial effectiveness☆

Abstract: This study examines the role of broad scope information, made available by management accounting systems (MAS), in enhancing managerial performance. It is proposed that differentiation of activities into areas such as marketing and production is an organizational response to manage uncertainty. The paper argues that such differentiation of activities moderates the association between the extent to which managers use broad scope MAS information and performance. A study of 75 managers indicated that the association between the extent of use of broad scope MAS information and performance was stronger for managers of marketing than production activities.

Antennas for use in portable communications devices

Abstract: Antenna arrangements for use with portable communications devices are described. In one embodiment, an antenna (50) has four equally spaced monopole elements (52-58) mounted in a regular array on the outer surface of a solid cylinder structure (60). The cylindre (60) has a high dielectric constant, and extends from a conductive ground plane (62). The monopole elements (52-58) can be switched by switching elements (64-70, 76) so that one or more is active, with the others acting as parasitic directors/reflectors being connected commonly to ground or left in an open circuit condition to be effectively transparent. A shielded single monopole antenna (10) is also described.

Describing and explaining research productivity

Abstract: This article describes results from a study of academic productivity in Australian higher education. It estimates the output (in terms of quantity of publications) of individual staff and academic departments across different subject areas and types of institution. Concerning research productivity, Australian academics resemble their colleagues in other countries: the average is low, while the range of variation is high. Most papers are produced by few academic staff. Several potential correlates of productivity, including level of research activity, subject area, institutional type, gender, age, early interest in research, and satisfaction with the promotions system, are examined. A model linking departmental context to personal research performance through department and personal research activity is developed and tested. The results support the view that structural factors (such as how academic departments are managed and led) combine with personal variables (such as intrinsic interest in the subject matter of one's discipline) to determine levels of productivity. There is also evidence that research and teaching do not form a single dimension of academic performance.

Harmonic-potential theorem: Implications for approximate many-body theories.

Abstract: We consider interacting particles in an external harmonic potential. We extend the $B=0$ case of the generalized Kohn theorem, giving a "harmonic-potential theorem" (HPT), demonstrating rigid, arbitrary-amplitude, time-oscillatory Schr\"odinger transport of a many-body eigenfunction. We show analytically that the time-dependent local-density approximation (TDLDA) satisfies the HPT exactly. Other approximations, such as linearized TDLDA with frequency-dependent exchange correlation kernel and certain inhomogeneous hydrodynamic formalisms, do not. A simple modification permits such explicitly frequency-dependent local theories to satisfy the HPT, however.

Ball and Socket Nanostructures: New Supramolecular Chemistry Based on Cyclotriveratrylene

Abstract: This paper outlines new vistas for the inclusion chemistry of hosts based upon the cyclotriveratrylene motif. A simple method of retrieving pure fullerenes from fullerite without the use of chromatographic techniques has been outlined, and a new class of ball and socket-type inclusion species has been realized by simple modification of either host or guest electronic and steric properties. 14 refs., 2 figs.

Current Educational Reform and the Significance of Problem-Based Learning.

Abstract: The present predicament of higher education resulting from government-imposed reforms is, it is argued, partly a consequence of the education to which members of government have themselves been subject; consequently, higher education carries some responsibility for the nature of the reforms. Government and higher education share a conception of knowledge, understanding and education which, paradoxically, predisposes the parties to act in opposed ways in regard to educational reform. Problem-based learning, understood in a problem-focused way, avoids significant features of the conception and points to more constructive ways of thought and action. Problem-focused understanding is significant for the light it throws on the general nature of current reforms and their implementation, for the prospect it offers of dealing constructively with changes resulting from reforms, and for longer-term benefits for both education and the wider community.

Fuzzy B-spline membership function (BMF) and its applications in fuzzy-neural control

Abstract: A general methodology for constructing fuzzy membership functions via B-spline curves is proposed. By using the method of least-squares, the authors translate the empirical data into the form of the control points of B-spline curves to construct fuzzy membership functions. This unified form of fuzzy membership functions is called a B-spline membership function (BMF). By using the local control property of a B-spline curve, the BMFs can be tuned locally during the learning process. For the control of a model car through fuzzy-neural networks, it is shown that the local tuning of BMFs can indeed reduce the number of iterations tremendously. This fuzzy-neural control of a model car is presented to illustrate the performance and applicability of the proposed method. >

Paramagnetic bis(1,4-di-tert-Butyl-1,4-Diazabutadiene) Adducts of Lithium, Magnesium, and Zinc

Abstract: Treatments of activated magnesium and zinc, M*, in THF and of sonified bulk lithium in hexane with 1,4-dizerz-butyl-1,4-diazabutadiene (Bu'2DAB) afford [M(Bu‘2DAB)2] as triplet, ligand-centered biradicals in the solid state and at low temperature in solution (M = Mg (1) (previously studied using EPR), Zn (2)) or a ligand-centered radical ( = Li (3) (gav = 2.0034 in hexane,

Sensing odour trails for mobile robot navigation

Abstract: By monitoring or following trails layed on the ground a mobile robot can perform several useful navigation tasks. An example would be following a trail layed on an outward journey in order to later find the way back to the starting point. This paper describes the latest stage in the development of a robot navigation system based on laying down and detecting trails of volatile chemicals. Previously a prototype olfactory sensor was developed which showed the feasibility of having a mobile robot follow an odour trail on the floor. This prototype sensor has now been improved by managing airflow in the vicinity of the sensor. This has decreased the sensor response time and improved rejection of spurious odour signals carried by airflow in the room. A simple and effective applicator has also been developed for laying odour trails. >

Topographic patterns of responsiveness to odorants in the rat olfactory epithelium

Abstract: 1. Regional differences in odorant-induced responsiveness of the rat olfactory epithelium were measured via electrophysiological recordings [negative component of electro-olfactogram (Veog(-)) made from the surface of the olfactory epithelium on the nasal septum]. The nasal septum provided a flat surface from which multiple recordings could be made. 2. Veog(-)s were recorded from a standardized grid of 16 sites. This grid of recording sites extended over most of the surface of the olfactory epithelium on the nasal septum. 3. Twenty-one animals were tested for their responses to seven odorants. The animals were divided into three groups, each of which was tested with two different odorants plus amyl acetate, which provided a comparison between the groups. 4. For each odorant in each animal, topographic maps of relative responsiveness were derived to test whether odorants elicited different patterns of responses in the same individual. Topographic maps of responsiveness were derived also for the animal groups to test for the generality of the form of the maps for different odorants. Response latencies were also measured for each odorant at each recording site. 5. All individuals showed different topographic patterns of responses to the three test odorants. For most odorants, the location of the most responsive site was similar in all animals. In different animals the topographic maps for the same odorant were remarkably similar. Topographic maps for the odorants were all different from one another. 6. These results are consistent with the hypothesis that odorant quality is encoded in the differential spatial distribution of receptor cells whose differences in responsiveness appear to be distributed as a continuum across the epithelium. The results establish for a mammalian species what was previously reported in amphibians. These differences are presumed to be due to differential expression of odorant receptor proteins. 7. The mean response latency was 32 ms. This period was similar for all odorants, all animals, and all recording sites and was independent of Veog(-) amplitude. It is concluded that diffusion through the mucus contributed approximately 6 ms to the latency of onset of the responses to these odorants.

The Relationship between Andragogical and Pedagogical Orientations and the Implications for Adult Learning

Abstract: Current literature suggests that the relationship between andragogy and pedagogy is based on a continuum. This study found that the relationship of andragogical and pedagogical orientations, measured by the Student's Orientation Questionnaire, is more correctly represented as being oithogonalorat right angles to each other. Such an orthogonal relationship reflects the complexities involved in adult learning. The paper discusses implications for both the learning process and for future research.

Transformational Change: Towards an Action Learning Organization

Abstract: Synthesizes the ideas of the “transformational change” and “learning organization” literature. The concept of the action learning organization is presented as a bridge between learning and transformation as it involves collaborative questioning by organizational members of their own actions. Discusses the characteristics of an action learning organization in terms of its bias for reflection‐in‐action, formation of learning alliances, development of external networks, multiple reward systems, creation of meaningful information, individual empowerment, leadership and vision. The knowledge‐generating organization is the one which is most likely to be able to survive both equilibrium and chaos.

Odor sensing for robot guidance

Abstract: There is no generally applicable technique for finding the position of an autonomous mobile robot operating in an un structured or varying environment. This article describes a project to investigate the use of short-lived navigational mark ers consisting of olfactory chemicals to guide mobile robots and to help them search and explore efficiently. Such a method of laying a trail to mark the path of a robot provides differ ential navigational information relative to the starting point and starting direction. Many insects employ olfactory cues as navigation aids and to improve their efficiency when searching for food. Three scenarios are proposed in which navigational markers can be of assistance to a mobile robot. The design and characteristics of an adsorbed mass olfactory sensor are described. This sensor was designed to be mounted on a mo bile robot and is suitable for detecting and tracking olfactory chemicals. The performance of this sensor is described together with preliminary results of using it t...

Network Representations of Knowledge about Chemical Equilibrium: Variations with Achievement.

Abstract: This study examined variation in the organization of domain-specific knowledge by 50 Year-12 chemistry students and 4 chemistry teachers. The study used nonmetric multidimensional scaling (MDS) and the Pathfinder network-generating algorithm to investigate individual and group differences in student concepts maps about chemical equilibrium. MDS was used to represent the individual maps in two-dimensional space, based on the presence or absence of paired propositional links. The resulting separation between maps reflected degree of hierarchical structure, but also reflected independent measures of student achievement. Pathfinder was then used to produce semantic networks from pooled data from high and low achievement groups using proximity matrices derived from the frequencies of paired concepts. The network constructed from maps of higher achievers (coherence measure = 0.18, linked pairs = 294, and number of subjects = 32) showed greater coherence, more concordance in specific paired links, more important specific conceptual relationships, and greater hierarchical organization than did the network constructed from maps of lower achievers (coherence measure = 0.12, linked pairs = 552, and number of subjects = 22). These differences are interpreted in terms of qualitative variation in knowledge organization by two groups of individuals with different levels of relative expertise (as reflected in achievement scores) concerning the topic of chemical equilibrium. The results suggest that the technique of transforming paired links in concept maps into proximity matrices for input to multivariate analyses provides a suitable methodology for comparing and documenting changes in the organization and structure of conceptual knowledge within and between individual students.

The demand for transport and communication in the United Kingdom and Australia

Abstract: This paper investigates the substitution/complementarity relationship among the demands for private transport, public transport and communication in the United Kingdom and Australia for the period 1960–1986. We use the Rotterdam Demand System for the analysis. The results identify major similarities and some important differences in consumption of these goods in the two countries. Further, they show that in both countries (a) private transport is a luxury and public transport is a necessity; (b) the demand for all three goods are price inelastic and (c) public transport, private transport and communications are pair-wise substitutes.

Acanthochromis polyacanthus, a fish lacking larval dispersal, has genetically differentiated populations at local and regional scales on the great-barrier-reef

Abstract: Acanthochromis Gill is a monotypic genus within the damselfish family Pomacentridae, erected for an unusual species [A. polyacanthus (Bleeker)] that uniquely lacks larval dispersal. Instead, offspring are reared in the parental territory, in the manner of cichlids, and fledged into the surrounding habitat. Phenotypic and genotypic variation was surveyed on the basis of body colouration and 7 polymorphic loci in 19 populations from 5 regions of the central and southern Great Barrier Reef (GBR). Variation in both characters was found at regional and local scales. Two colour morphs were recognised: a bicoloured morph from the three northern regions and a uniform dark morph from the two southern regions. Isozyme analysis showed a similar pattern with greatest variation between the different morphs, but also with significant variation at both regional and local scales within morphotypes. Heterozygosity was maximal in the central populations, which, together with other measures of variability, suggests a mixing of separate gene pools in this region and denies species status to the two morphotypes despite numerous fixed differences in allele frequencies between the most distant populations. The presence of fixed differences in multiple alleles between populations separated by 1000 km indicates negligible gene flow over such distances and long isolation of these gene pools. These patterns may reflect recolonisation of the GBR after the last sea-level rise by fish from two stocks. Founder effects and random drift in small populations after colonisation are probably the major sources of the local and regional variations observed at smaller spatial scales. This diversity has been maintained among populations at all scales by the very low levels of gene flow possible without an effective strategy for larval dispersal between coral reefs.

Participation in Leisure Activities after the Death of a Spouse

Abstract: The main purpose of this exploratory study was to establish whether frequent participation in leisure activities helped widows and widowers adapt to widowhood. The study also examined whether more frequent participation in leisure activities by widows and widowers helped them maintain higher morale. A small sample of 60 recently bereaved widows and widowers who were living independently in a state capital in Australia was selected for the study. Each widow or widower was interviewed and provided responses to three scales measuring participation in leisure activities, adaptation to widowhood, and morale. Quantitative and qualitative research techniques were used to interpret the data. The leisure activities most frequently participated in by widows and widowers were found to be home‐based activities and mainly involved social activities with family and friends. Greater participation in leisure activities, especially with family and friends, was found to be significantly related to increased morale...

Strategic perspectives analysis: A procedure for participatory and political social impact assessment

Abstract: Recent developments in planning and social impact assessment (SIA) theory have traveled parallel paths. Both fields have moved away from centralized, purportedly apolitical modes of decision making and are moving toward enhanced participation of parties affected by resource development. Some writers now view SIA and planning as essentially sociopolitical processes that should facilitate bargaining and negotiation among interest groups within the constraints of the law and government administration. Strategic perspectives analysis has been designed as a flexible procedure that can be used to conduct both participatory and political applications of SIA. In a progression from position analysis techniques, the method uses strategic planning principles to elicit the vision, objectives, and strategies of each party. It then facilitates the articulation of their interests with the planning process through more effective bargaining and negotiation.

The implementation of problem–based learning: changing pedagogy in nurse education

Abstract: Problem-based learning (PBL) employs approaches to teaching and learning in nurse education that develop meaningful links between theory and practice The adoption of such approaches, however, may require changes in pedagogical beliefs and practices which reflect a student-centred approach to teaching and learning This paper focuses on a group of volunteer nurse educators (n= 14) who attended a 7-month professional development programme centred on introducing pedagogical changes when adopting PBL From this group, three nurse educators participated in an in-depth study which aimed to examine the processes of conceptual change associated with adopting PBL as part of alternative teaching strategies These three participants held common concerns about the changes required to their current teaching practices when moving to a new pedagogical approach On completion of the programme, varying degrees of change in existing instructional practices were evident This change was found to result from engaging educators in reflection about practice, providing opportunities to implement the new approaches on a trial basis, and providing feedback and support throughout the change process

Marketing in the public sector: Inappropriate or merely difficult?

Abstract: Economic and political imperatives of the 1980s have seen governments turn to private sector managerial techniques, practices and orientations to enable them to deliver services more efficiently and effectively. Among these is marketing which has received increasing attention as governments have looked to privatize, corporatize or simply introduce some level of “user‐pays” principle into their operations. Despite the ambitious claims of the marketing discipline, the transposition of marketing to the public sector has not proved to be without problems. This paper reviews why such a transposition might be difficult. It also reviews the claim of marketing to be an appropriate discipline at all for widespread application in the public sector. The paper concludes that marketers should be cautious as to the extent to which their discipline can be transposed or modified to assist governments identity, plan, deliver and evaluate services more efficiently and effectively.

Communicative Aspects of the Service Encounter

Abstract: Ninety-six subjects listened to audio tapes of hotel reservationists taking a telephone inquiry using different communication styles and different levels of role competence. Results showed a convergent style of communication was rated more highly, especially at lower levels of role competency. Sex of subject also influenced the ratings of the reservationists, with female subjects generally giving higher ratings than male subjects. Although product knowledge is important, more attention should be paid to training service providers in how to communicate that knowledge.

Tourists′ Perceptions of Service in Shops:

Abstract: Presents the results of an exploratory study on Japanese tourists′ perceptions of service quality in Australian shops. Eight areas of service were examined: the shop assistants′ friendliness, politeness, information giving, helpfulness, concern about customers, ability to speak Japanese, ability to wrap goods, and financial exploitation. It was found that in four out of eight areas of service – information giving, helpfulness, concern about tourists′ needs and ability to speak the Japanese language‐there were significant differences between tourists′ pre‐travel expectations and post‐travel perceptions of service. Explores the implications of these findings for the retail sector and outlines recommendations.

Situating Learning in the Workplace – Having Another Look at Apprenticeships

Abstract: Examines the acquisition of vocational skills through apprenticeship‐type situated learning. Presents findings from studies of skilled workers revealing that learning processes that were consonant with the apprenticeship model of learning were highly valued as a means of acquiring and maintaining vocational skills. Supported by current research and theorizing, describes some conditions by which situated learning through apprenticeship can be utilized to develop vocational skills. These conditixons include the nature of the activities learners engage in, the agency of the learning environment and mentoring role of experts. Addresses conditions which may inhibit the effectiveness of an apprenticeship approach to learning. Concludes by suggesting that situated approaches to learning, such as the apprenticeship model, may address problems of access to effective vocational skill development within the workforces.