Business Management 312
- Authors: Fatoki, O O , Rowles, M
- Date: 2008-08
- Language: English
- Type: Examination paper
- Identifier: vital:17431 , http://hdl.handle.net/10353/d1010241
- Description: Business Management: BEC 312 / 312E, August 2008.
- Full Text: false
- Date Issued: 2008-08
A tuple space web service for distributed programming-Simplifying distributed web services applications
- Authors: Wells, George C , Mueller, Barbara , Schulé, Lo¨ıc
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430437 , vital:72691 , https://www.scitepress.org/PublishedPapers/2008/15170/15170.pdf
- Description: This paper describes a new tuple space web service for coordination and communication in distributed web applications. This web service is based on the Linda programming model. Linda is a coordination lan-guage for parallel and distributed processing, providing a communica-tion mechanism based on a logically shared memory space. The origi-nal Linda model has been extended through the provision of a pro-grammable mechanism, providing additional flexibility and improved performance. The implementation of the web service is discussed, to-gether with the details of the programmable matching mechanism. Some results from the implementation of a location-based mobile appli-cation, using the tuple space web service are presented, demonstrating the benefits of our system.
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- Date Issued: 2008
Automating the creation of 3D animation from annotated fiction text
- Authors: Glass, Kevin R , Bangay, Shaun D
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/432639 , vital:72889 , https://www.iadisportal.org/digital-library/automating-the-creation-of-3d-animation-from-annotated-fiction-text
- Description: This paper describes a strategy for automatically converting fiction text into 3D animations. It assumes the existence of fiction text annotated with avatar, object, setting, transition and relation annotations, and presents a transformation process that converts annotated text into quantified constraint systems, the solutions to which are used in the population of 3D environments. Constraint solutions are valid over temporal intervals, ensuring that consistent dynamic behaviour is produced. A substantial level of automation is achieved, while providing opportunities for creative manual intervention in animation process. The process is demonstrated using annotated examples drawn from popular fiction text that are converted into animation sequences, confirming that the desired results can be achieved with only high-level human direction.
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- Date Issued: 2008
Baited traps may be an alternative to conventional pesticides in the integrated crop management of chicory (Compositae) in South Africa
- Authors: Midgley, John M , Hill, Martin P , Villet, Martin H
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6858 , http://hdl.handle.net/10962/d1011141 , http://dx.doi.org/10.1603/0022-0493(2008)101[99:BTMBAA]2.0.CO;2 , https://orcid.org/0000-0003-0579-5298
- Description: Chicory, Chicorium intybus L. (Compositae), is a major field crop in the Eastern Cape Province of South Africa. Several pests feed on the leaves of the plant, resulting in reduced yield. The most important of these are the noctuid moths Helicoverpa armigera (Hübner), Chrysodeixis acuta (Walker), and Trichoplusia orichalcea (F.). The use of attract-and-kill traps offers an alternative to broad-based insecticides in the control of these species. Three fields were treated with normal insecticides and three fields with yellow-baited traps. Eight additional traps were placed in each field, with half of the traps containing the insecticide 2,2-dichlorovinyl dimethyl phosphate (dichlorvos) and half without dichlorvos; and half yellow and half green. Total moth numbers and nonphytophage diversity were measured from these eight traps. Although no differences in H. armigera or T. orichalcea catches were observed between insecticide- and trap-treated fields, numbers of C. acuta and the total number of moths were significantly higher in insecticide-treated fields. Yellow traps containing dichlorvos contained more moths than yellow traps without dichlorvos, or green traps with dichlorvos, or green traps without dichlorvos; but they also contained more nonphytophagous insects. Yellow traps also enhanced the catches of thrips on card traps associated with them. These results offer an opportunity for the South African chicory industry to reduce pesticide applications and thus mitigate environmental impacts.
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- Date Issued: 2008
Biological responses to a resumption in river flow in a freshwater-deprived, permanently open Southern African estuary
- Authors: Vorwerk, Paul D , Froneman, P William , Paterson, Angus W , Strydom, Nadine A , Whitfield, Alan K
- Date: 2008
- Language: English
- Type: text , Article
- Identifier: vital:6886 , http://hdl.handle.net/10962/d1011645
- Description: The Kariega Estuary is a freshwater-deprived system due to numerous impoundments in the catchment. This system has had little or no horizontal salinity gradient over the last 15 years, with hypersaline conditions sometimes predominating in the upper reaches. Following high rainfall events in the catchment during the spring of 2006, including a flood event (approximate 1:10 year) in August 2006, a series of riverine pulses entered the estuary and a horizontal salinity gradient was established. This study examined the influence of this freshwater pulse on four components of the biota within the estuary, namely the zooplankton, and larval, littoral and demersal fishes. The study demonstrated that in three of these components elevated densities were recorded following the riverine input, with only the littoral fishes retaining an almost constant density. In addition, changes in the relative contributions of the estuarine utilisation classes for all three fish groups examined indicated that freshwater input into these systems positively influences the abundances. This has significant implications for water managers as it demonstrates the importance of an Ecological Reserve (defined as ‘the water required to protect the aquatic ecosystems of the water resource’) for this system.
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- Date Issued: 2008
Demand-side management of internet bandwidth
- Authors: Halse, Guy A
- Date: 2008
- Language: English
- Type: Conference paper
- Identifier: vital:6607 , http://hdl.handle.net/10962/d1009463
- Description: Presentation on the demand-side management of Internet bandwidth, using Rhodes University as a case study, as presented at the DITCHE national techie event in September 2008.
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- Date Issued: 2008
Factors affecting accuracy and precision of thermal summation models of insect development used to estimate post-mortem intervals
- Authors: Richards, Cameron S , Villet, Martin H
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442142 , vital:73962 , https://doi.org/10.1007/s00414-008-0243-5
- Description: This paper investigates the effects that different summary statistics (minimum, median, mean, or maximum), temporal sampling resolutions (duration between sampling events), and sample sizes (number of individuals sampled per sampling event) had on the accuracy and precision of the regression coefficients of a typical thermal summation model used to calculate minimum post-mortem interval (PMI). No significant differences were found in the values of the developmental constants calculated from different summary statistics of the duration of development. Sample size was found to affect the precision of measurement of the duration of development but had little overall influence on thermal summation constant (K) and developmental threshold (D 0) calculations (and therefore, subsequent PMI estimates), but temporal sampling resolution had a direct influence on the accuracy of K and D 0 calculations. These data suggest that when numbers of experimental maggots are limited, it is more important to sample more frequently using smaller sample sizes than to sample less frequently with large sample sizes. Furthermore, we suggest that the median is the most representative summary measure of the duration of development and should be used preferentially.
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- Date Issued: 2008
Hydrolytic enzymes in sewage sludge treatment: a mini-review
- Authors: Burgess, Jo E , Pletschke, Brett I
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6478 , http://hdl.handle.net/10962/d1006166 , http://hdl.handle.net/10520/EJC116535
- Description: Biological wastewater treatment processes can be classified as either aerobic or anaerobic. These two biological treatment processes are each characterised by groups of micro-organisms and their associated enzymes. Hydrolytic enzymes secreted by these micro-organisms are vital for the rate-limiting step of hydrolysis in the treatment of highly polymeric substrates present in sewage sludge. In this mini-review, the effects of mass transfer limitation, metabolic intermediates, extracellular polymeric substances (EPS), electron acceptor conditions and pH and temperature on the activity of these enzymes are summarised. The most salient and current perspectives of the significance and the role that hydrolytic enzymes play in sewage sludge treatment are highlighted.
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- Date Issued: 2008
Study of the formation of artifacts following Dichloromethane reaction with some nitrogenous drugs
- Authors: Mohammadi, Ali , Amini, Mohsen , Hamedani, Moteza P , Torkabadi, Hossein H , Walker, Roderick B
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6409 , http://hdl.handle.net/10962/d1006495
- Description: In this work, the quaternization reaction of some nitrogenous drugs in dichloromethane under stress condition and room temperature at different times are studied. Under these conditions, drug-chloromethochloride adducts or artifacts were found to be formed for clozapine, ofloxacin and olanzapine. The structures of the resultant adducts were elucidated using 1H NMR spectroscopy. In addition, the amount of intact drug was determined using in-house validated HPLC methods with UV detection.
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- Date Issued: 2008
The relationship between emergence of the shortest path and information value using ant-like agents
- Authors: Chibaya, Colin , Bangay, Shaun D
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433318 , vital:72961 , https://doi.org/10.1145/1456659.1456663
- Description: Ant-like agents forage between two points. These agents' probabilistic movements are based on the use of two pheromones; one marking trails towards the goal and another marking trails back to the starting point. Path selection decisions are influenced by the relative levels of attractive and repulsive pheromone in each agent's local environment. Our work in [5] evaluates three pheromone perception strategies, investigating path formation speed, quality, directionality, robustness and adaptability under different parameter settings(degree of randomness, pheromone evaporation rate and pheromone diffusion rate).
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- Date Issued: 2008
Viewpoint: reading conference recommendations in a wider context of social change
- Authors: Lotz-Sisitka, Heila
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67411 , vital:29085 , https://www.ajol.info/index.php/sajee/article/view/122783
- Description: publisher version , This short Viewpoint paper considers the role and value of conference recommendations in shaping the field of environmental education. It explores the social politics, and often contested nature, of conference recommendations and their institutional histories, arguing that the act of producing conference recommendations forms part of the practices of new social movements. The paper recommends historicising conference recommendations and OEcross readings‚ to consider changing discourses and new developments in the field. Accompanying the short Viewpoint paper, are two sets of recently produced conference recommendations, one from the 4th International Environmental Education Conference held in Ahmedabad, India, and the other from the 1st International Conference on Mainstreaming Environment and Sustainability in African Universities held in Nairobi, Kenya.
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- Date Issued: 2008
Women’s rights get a dressing down: mini skirt attacks in South Africa
- Authors: Vincent, Louise
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141888 , vital:38013 , DOI: 10.18848/1447-9508/cgp/v06i06/42462
- Description: On Sunday the 17th of February 2008 25-year old Nwabisa Ngcukana was stripped, paraded naked while more than 100 onlookers jeered and laughed, doused in alcohol and sexually assaulted by taxi drivers and hawkers at the Noord Street taxi rank in Johannesburg1 (The Star 2008: 2). She was the fourth woman to be assaulted in this way at the rank on that evening. Three other women were stripped and sexually assaulted at the same taxi rank on the previous day. In each of these cases the fact that the women were wearing mini skirts was cited as the reason for the attack.
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- Date Issued: 2008
An ontology-based, multi-modal platform for the inclusion of marginalized rural communities into the knowledge society
- Authors: Thinyane, Mamello , Dalvit, Lorenzo , Slay, Hannah , Mapi, Thandeka , Terzoli, Alfredo
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431218 , vital:72755 , https://doi.org/10.1145/1292491.1292508
- Description: With the information revolution that promises to shape the 21st century, knowledge has become the prime commodity, very much like land, means of production and capital have been at different times in the past. Access to information, made instantly available by the growth of the Internet, determines access to economic resources, social participa-tion and better quality of life. For this reason, the knowledge stored on the Web and the advantages offered by the spread of Information and Communication Technology (ICT) are equally important for rich socie-ties to prosper and for poor ones to develop. The only difference is that marginalised communities do not have access to the tools and have little control over the content found in the domain of ICTs. In this paper we describe an intervention to develop the potential of a typical rural community in South Africa through ICTs. This involves providing Inter-net connectivity and deploying a platform to support e-commerce, e-learning, e-government and e-health. The core of the platform is an on-tology-based model designed to integrate and respond to Indigenous Knowledge Systems. This has been achieved by combining a deep understanding of local knowledge and social networks with the use of authoring, communication and ontology-management tools. The prima-ry goal of this new approach is to find a way to make ICT solutions more sensitive to the local context, and therefore more effective. Sec-ondly, we hope to foster a sense of ownership of the project among the community, by capitalising on local knowledge and resources.
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- Date Issued: 2007
Animated feather coats using field lines
- Authors: Bangay, Shaun D
- Date: 2007
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/433338 , vital:72963 , https://doi.org/10.1145/1294685.1294713
- Description: The tedious task of manually placing feathers on computer animated ob-jects involves aligning feathers, ensuring that they do not insect each other or penetrate the surface, deforming every feather to match the local surface features, and ensuring that the feather coat is consistent when the underly-ing object is animated. We present a technique for generating a feather coat over an object. Feather orientation is specified quickly and easily, feathers are deformed while ensuring collision prevention, and the coat can be ani-mated. We create a vector field in the space surrounding the body object and deform feathers to align with the field lines. The non-intersection proper-ty of the field lines ensures that feather intersections are avoided. We pro-vide a formulation of a suitable vector field and demonstrate that it is capa-ble of producing realistic feather coats. The process can easily be integrated into the work-flow of standard modelling and animation processes. We show examples of feather coat creation on a range of objects, proving that field line based placement of feather coats provides the desired functionality for feather modelling and animation.
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- Date Issued: 2007
Bi-Alexandroff spaces
- Authors: Matutu, Phethiwe P
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6782 , http://hdl.handle.net/10962/d1006925
- Description: Bi-Alexandroff spaces are defined as extensions of Alexandroff spaces [1]. Urysohn’s lemma for bi-Alexandroff spaces is used to show that upper and lower cozero sets of bitopological spaces are bi-Alexandroff spaces. An adjunction between bi-Alexandroff spaces and pairwise completely regular bitopological spaces is established.
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- Date Issued: 2007
Does 'African mathematics' facilitate access to mathematics?: towards an ongoing critical analysis of ethnomathematics in a South African context
- Authors: Horsthemke, Kai , Schäfer, Marc
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141004 , vital:37936 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC20885
- Description: Mosibudi Mangena, the Minister of Science and Technology, said in an address to the Annual Congress of the South African Mathematical Society at the University of the Potchefstroom, November 2, 2004: "There is one thing we need to address before anything else. We need to increase the number of young people, particularly blacks and women, who are able to successfully complete the first course in Mathematics at our universities." How is this to be achieved? A popular trend involves a call for the introduction and incorporation of so-called ethnomathematics, and more particularly 'African mathematics', into secondary and tertiary curricula. Although acknowledging the obvious benefits of so-called ethnomathematics, this paper critically analyses three aspects of ethnomathematics that have been neglected in past critiques. Our focus is not on the relationship as such between ethnomathematics and mathematics education. Our critique involves (1) epistemological and logical misgivings, (2) a new look at practices and skills, (3) concerns about embracing 'African mathematics' as valid and valuable - just because it is African.
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- Date Issued: 2007
Does the endangered Knysna seahorse, Hippocampus capensis, have a preference for aquatic vegetation type, cover or height?
- Authors: Teske, Peter R , Lockyear, Jaqueline F , Hecht, Thomas , Kaiser, Horst
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6775 , http://hdl.handle.net/10962/d1008082
- Description: The Knysna seahorse, Hippocampus capensis, is an endangered teleost confined to three South African estuaries. Its abundance within these systems is low and distributions are patchy. Consequently, monitoring population sizes is labour-intensive. The aim of this study was to establish if Knynsa seahorses are associated with specific regions within the estuaries, on which conservation efforts could concentrate. The relationship of Knysna seahorses with aquatic vegetation was analysed in the Knysna Estuary (the largest of the three estuarine systems inhabited by H. capensis) to determine whether this species shows a preference for a particular plant species, vegetation density or vegetation height. Seahorses were associated with five dominant aquatic plants: Zostera capensis, Caulerpa filiformis, Codium extricatum, Halophila ovalis and Ruppia cirrhosa. Together, these comprised 96% of the submerged objects with which seahorses were associated. The relative abundance of plant species changed along the estuary, but seahorses were present throughout the system, except at the estuary mouth, which was characterized by low plant densities and strong currents. No significant difference was found between the proportion of plant species present in a particular region of the estuary and the proportion of plants that seahorses used as holdfasts. However, when Z. capensis and C. filiformis were present at the same sites, adult seahorses preferred C. filiformis as holdfast. Adult seahorse density (individuals/m²) was significantly correlated with percentage vegetation cover and with holdfast length, but juvenile seahorse density was not. Nonetheless, significantly more adult and juvenile seahorses were found at sites characterized by high vegetation cover (>75%) than at sites with lower cover. Our results indicate that although there is some evidence that Knynsa seahorses prefer certain plant species over others, they are likely to be encountered anywhere in the estuary where aquatic plants are present. Conservation efforts in the Knysna Estuary should thus concentrate on such vegetated areas, which comprise approximately 11% of the total submerged surface area.
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- Date Issued: 2007
Language policy and planning: general constraints and pressures
- Authors: Wright, Laurence
- Date: 2007
- Language: English
- Type: text , article
- Identifier: vital:7043 , http://hdl.handle.net/10962/d1007385
- Description: preprint , The general idea of language policy and planning is easily expressed. Christopher Brumfit, for one, defines language planning as “The attempt to control the use, status, and structure of a language through a language policy developed by a government or other authority” (see the Oxford Companion to the English Language). The Random House Dictionary of the English Language concurs, but adds some detail: language planning is “the development of policies or programmes designed to direct or change language use, as through the establishment of an official language, the standardization or modernization of a language, or the development or alteration of a writing system”. Such definitions could easily be multiplied, and they differ only slightly in nuance and depth.Language Policy is the formal, often legally entrenched, expression of language planning.
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- Date Issued: 2007
Rhodes University 2007 Graduation Ceremonies Address
- Authors: Badat, Saleem
- Date: 2007
- Subjects: Rhodes University
- Language: English
- Type: Text
- Identifier: vital:7628 , http://hdl.handle.net/10962/d1012595
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- Date Issued: 2007
Spatial and seasonal distribution patterns of juvenile and adult raggedtooth sharks (Carcharias taurus) tagged off the east coast of South Africa
- Authors: Dicken, Matthew L , Booth, Anthony J , Smale, Malcolm J , Cliff, G
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126997 , vital:35942 , https://doi.10.1071/MF06018
- Description: Crucial to effective fisheries management is a thorough understanding of the stock structure of a population. Understanding the spatial and seasonal distribution patterns of a species is necessary to define habitat use and evaluate the potential effects of exploitation and anthropogenic activities. This is particularly important for a species such as the raggedtooth shark (Carcharias Taurus Rafinesque, 1810), whose life-history characteristics make it particularly susceptible to over-exploitation (Pollard et al. 1996; Smith et al. 1998; Compagno 2001). Exploitation, even at low levels for a slow-growing, late-maturing species that only produces two pups every other year, could reduce the population growth rate, could reduce the population growth rate to values of λ<1.0, resulting in severe population declines in a very short time period (Baum et al. 2003).
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- Date Issued: 2007