Using virtual reality to monitor and control an industrial robot via the Internet
- Authors: Vermeulen, Heinrich
- Date: 2001
- Subjects: Virtual reality , Robotics -- Computer programs
- Language: English
- Type: Thesis , Masters , MTech (Engineering)
- Identifier: vital:10820 , http://hdl.handle.net/10948/74 , Virtual reality , Robotics -- Computer programs
- Description: Manufacturing processes may be modeled in various ways, including 3D modeling. There is a need to visualise, control and monitor manufacturing processes remotely via the Internet. Virtual Reality (VR) can be described as the science of integrating man with information. It is based on three distinct environments: three-dimensional, interactive and computer-generated. VR has come to the Internet in the form of VR modeling. The evolution of Web technologies in recent years has enabled the use of VR modeling for visualisation of manufacturing processes. The VR modeling language (VRML), which has become the standard for transmitting 3D virtual worlds across the Internet, can be used to control and monitor manufacturing processes visually. A 3D model of a manufacturing process, specifically an industrial robot arm, was created for this project. This model was successfully linked to the industrial robot that it represents in order to control and monitor the robot’s actions remotely via the Internet using Web technologies. This dissertation proves the viablity of using Virtual Reality to effectively visualise, monitor and control an industrial robot via the Internet. It also describes the methodology that was followed in modeling the industrial robot arm in VRML as well as linking the model to the real world application.
- Full Text:
- Date Issued: 2001
- Authors: Vermeulen, Heinrich
- Date: 2001
- Subjects: Virtual reality , Robotics -- Computer programs
- Language: English
- Type: Thesis , Masters , MTech (Engineering)
- Identifier: vital:10820 , http://hdl.handle.net/10948/74 , Virtual reality , Robotics -- Computer programs
- Description: Manufacturing processes may be modeled in various ways, including 3D modeling. There is a need to visualise, control and monitor manufacturing processes remotely via the Internet. Virtual Reality (VR) can be described as the science of integrating man with information. It is based on three distinct environments: three-dimensional, interactive and computer-generated. VR has come to the Internet in the form of VR modeling. The evolution of Web technologies in recent years has enabled the use of VR modeling for visualisation of manufacturing processes. The VR modeling language (VRML), which has become the standard for transmitting 3D virtual worlds across the Internet, can be used to control and monitor manufacturing processes visually. A 3D model of a manufacturing process, specifically an industrial robot arm, was created for this project. This model was successfully linked to the industrial robot that it represents in order to control and monitor the robot’s actions remotely via the Internet using Web technologies. This dissertation proves the viablity of using Virtual Reality to effectively visualise, monitor and control an industrial robot via the Internet. It also describes the methodology that was followed in modeling the industrial robot arm in VRML as well as linking the model to the real world application.
- Full Text:
- Date Issued: 2001
Valuing South Africa's savannas: Methodological Issues
- Ballance, A, Shackleton, Charlie M, Shackleton, Sheona E, Geach, B S, Crookes, D, De Wit, M, Evans, J, von Maltitz, G, Willis, C B, Kelatwang, S, Havemann, J
- Authors: Ballance, A , Shackleton, Charlie M , Shackleton, Sheona E , Geach, B S , Crookes, D , De Wit, M , Evans, J , von Maltitz, G , Willis, C B , Kelatwang, S , Havemann, J
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182262 , vital:43816 , xlink:href="https://hdl.handle.net/10520/EJC33860"
- Description: Natural resource valuation techniques have been applied in recent years to savannas and savanna resources in South and southern Africa. Results from these studies have been used to demonstrate the importance of savannas, and to assist in resource-use planning. Because these studies have been conducted to meet different research objectives a large number of disparities exist between studies. This makes comparison of results difficult and identification of underlying drivers of value is problematic. This paper discusses issues which can lead to differences in estimates of resource value, and makes recommendations for future studies to reduce incompatibilities. In particular, this paper recommends that future studies make full descriptions of the objectives of the study, the background characteristics of the study area (including the social, political, economic, cultural, and biophysical characteristics), the methods used, and assumptions made. In this way, the values reported from case studies may be used in other research and decision-making exercises.
- Full Text:
- Date Issued: 2001
- Authors: Ballance, A , Shackleton, Charlie M , Shackleton, Sheona E , Geach, B S , Crookes, D , De Wit, M , Evans, J , von Maltitz, G , Willis, C B , Kelatwang, S , Havemann, J
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182262 , vital:43816 , xlink:href="https://hdl.handle.net/10520/EJC33860"
- Description: Natural resource valuation techniques have been applied in recent years to savannas and savanna resources in South and southern Africa. Results from these studies have been used to demonstrate the importance of savannas, and to assist in resource-use planning. Because these studies have been conducted to meet different research objectives a large number of disparities exist between studies. This makes comparison of results difficult and identification of underlying drivers of value is problematic. This paper discusses issues which can lead to differences in estimates of resource value, and makes recommendations for future studies to reduce incompatibilities. In particular, this paper recommends that future studies make full descriptions of the objectives of the study, the background characteristics of the study area (including the social, political, economic, cultural, and biophysical characteristics), the methods used, and assumptions made. In this way, the values reported from case studies may be used in other research and decision-making exercises.
- Full Text:
- Date Issued: 2001
Vein structure in relation to phloem loading in selected Ranunculaceae, Apocynaceae and Asclepiadaceae of the Eastern Cape
- Authors: Buswell, Alison Mary
- Date: 2001
- Subjects: Ranunculaceae Apocynaceae Asclepiadaceae Phloem Plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4243 , http://hdl.handle.net/10962/d1007277
- Description: The relationship between leaf architecture, vein anatomy and phloem ultrastructure, and that of possible routes from mesophyll cells to phloem and potential phloem loading method was investigated using species adapted to the southern African climate. The research was based on the hypothesis of Gamaiei and Van Bel, using nothern hemisphere species only (Gamalei 1985a, b, 1989, 1991, VanBeletal. 1988, Van Bel 1992, 1994, 1996, Van Bel & Gamalei 1991, 1992, Gamalei et al. 1992, 1994, 1996, Van Bel 1992a-c, 1993a, b, 1996). The thesis commenced with a survey ofleafarchitecture of the Ranunculaceae, Apocynaceae and Asclepiadaceae. Anatomical and ultrastructural studies followed. Leaf architecture was described according to Hickey (1973). Within the Ranuncuiaceae, leaf architecture was found to be marginally actinodromous. Venation pattern consisted of a widely spaced reticulum of delicate veins, especially in Ranunculus. Leaf architecture of the Apocynaceae was described as pinnate, camptodromous and brochidodromous. The Asclepiadaceae showed less uniformity in terms of leaf architecture, being pinnate and camptodromous, with mostly brochidodromous and, unexpectedly, eucamptodromous patterns of secondary venation. A predominantly common leaf architecture supported the move to amalgamate the two families. As the less advanced eucamptodromous arrangement could represent a more primitive branch of this huge family, the phylogenetic classification of the new amalgamated family is eagerly awaited for discussion. Allocation of vein order allowed comparisons between species and families to be drawn. Reticulum density and vein order anatomy was used to indicate potential routes from mesophyll to phloem. A definite contrast was obvious between the loose arrangement of mesophyll and veins in the mesic Ranunculus, and the close mesophyll and dense venation of the xeric apocynate and asclepiad species, and was related to habitat. Ultrastructural characteristics of companion cells, together with plasmodesmatal abundance, were considered especially important for the determination of minor vein configuration. Descriptions of plasmodesmatal distribution did not consider functional status. In this thesis, vein structure and ultrastructure were considered in relation to phloem loading, not as a demonstration thereof. All three families were designated minor vein configuration type 2a. Two interesting examples that did not adhere to the familial norm, viz. few plasmodesmata and normal companion cells, occurred in the Asclepiadaceae. Secamone alpinii had abundant aggregated plasmodesmata, forming a potential symplasmic continuum from mesophyll to companion cells. The question of plasmodesmatal functionality remained open. Ceropegia carnosa showed folding of the companion cell membrane, but no accompanying wall ingrowths. The folds were suggested to increase surface area for apoplasmic phloem loading in the noted absence of plasmodesmata. Loading routes and methods suggested were based on anatomical and ultrastructural evidence only. Whilst these results were supported by published data for other species of these families, the prediction of the Gamalei and Van Bel hypothesis did not hold true. The relatively primitive Ranunculaceae were expected to have the least advanced type 1 minor vein configuration, with abundance plasmodesmata providing a symplasmic phloem loading pathway. The relatively advanced Apocynaceae and Asc1epiadaceae were predicted to have the most progressive minor vein configuration, type 2b, with specialised transfer cells to maximise apoplasrnic uptake. As families with type 2a minor vein configurations, the Ranunculaceae were more advanced than expected and the Apocynaceae and Asc1epiadaceae less so.
- Full Text:
- Date Issued: 2001
- Authors: Buswell, Alison Mary
- Date: 2001
- Subjects: Ranunculaceae Apocynaceae Asclepiadaceae Phloem Plants -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4243 , http://hdl.handle.net/10962/d1007277
- Description: The relationship between leaf architecture, vein anatomy and phloem ultrastructure, and that of possible routes from mesophyll cells to phloem and potential phloem loading method was investigated using species adapted to the southern African climate. The research was based on the hypothesis of Gamaiei and Van Bel, using nothern hemisphere species only (Gamalei 1985a, b, 1989, 1991, VanBeletal. 1988, Van Bel 1992, 1994, 1996, Van Bel & Gamalei 1991, 1992, Gamalei et al. 1992, 1994, 1996, Van Bel 1992a-c, 1993a, b, 1996). The thesis commenced with a survey ofleafarchitecture of the Ranunculaceae, Apocynaceae and Asclepiadaceae. Anatomical and ultrastructural studies followed. Leaf architecture was described according to Hickey (1973). Within the Ranuncuiaceae, leaf architecture was found to be marginally actinodromous. Venation pattern consisted of a widely spaced reticulum of delicate veins, especially in Ranunculus. Leaf architecture of the Apocynaceae was described as pinnate, camptodromous and brochidodromous. The Asclepiadaceae showed less uniformity in terms of leaf architecture, being pinnate and camptodromous, with mostly brochidodromous and, unexpectedly, eucamptodromous patterns of secondary venation. A predominantly common leaf architecture supported the move to amalgamate the two families. As the less advanced eucamptodromous arrangement could represent a more primitive branch of this huge family, the phylogenetic classification of the new amalgamated family is eagerly awaited for discussion. Allocation of vein order allowed comparisons between species and families to be drawn. Reticulum density and vein order anatomy was used to indicate potential routes from mesophyll to phloem. A definite contrast was obvious between the loose arrangement of mesophyll and veins in the mesic Ranunculus, and the close mesophyll and dense venation of the xeric apocynate and asclepiad species, and was related to habitat. Ultrastructural characteristics of companion cells, together with plasmodesmatal abundance, were considered especially important for the determination of minor vein configuration. Descriptions of plasmodesmatal distribution did not consider functional status. In this thesis, vein structure and ultrastructure were considered in relation to phloem loading, not as a demonstration thereof. All three families were designated minor vein configuration type 2a. Two interesting examples that did not adhere to the familial norm, viz. few plasmodesmata and normal companion cells, occurred in the Asclepiadaceae. Secamone alpinii had abundant aggregated plasmodesmata, forming a potential symplasmic continuum from mesophyll to companion cells. The question of plasmodesmatal functionality remained open. Ceropegia carnosa showed folding of the companion cell membrane, but no accompanying wall ingrowths. The folds were suggested to increase surface area for apoplasmic phloem loading in the noted absence of plasmodesmata. Loading routes and methods suggested were based on anatomical and ultrastructural evidence only. Whilst these results were supported by published data for other species of these families, the prediction of the Gamalei and Van Bel hypothesis did not hold true. The relatively primitive Ranunculaceae were expected to have the least advanced type 1 minor vein configuration, with abundance plasmodesmata providing a symplasmic phloem loading pathway. The relatively advanced Apocynaceae and Asc1epiadaceae were predicted to have the most progressive minor vein configuration, type 2b, with specialised transfer cells to maximise apoplasrnic uptake. As families with type 2a minor vein configurations, the Ranunculaceae were more advanced than expected and the Apocynaceae and Asc1epiadaceae less so.
- Full Text:
- Date Issued: 2001
Voltammetric determination of nitric oxide on cobalt phthalocyanine modified microelectrodes
- Vilakazi, Sibulelo Lea, Nyokong, Tebello
- Authors: Vilakazi, Sibulelo Lea , Nyokong, Tebello
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/291629 , vital:56893 , xlink:href="https://doi.org/10.1016/S0022-0728(01)00583-6"
- Description: The catalytic activity of a carbon fiber microelectrode modified with cobalt phthalocyanine (CoPc-ME) for the detection of nitric oxide in the presence of possible interfering molecules (dopamine and serotonin) is examined. A linear plot is observed for the variation of the catalytic currents with NO concentration in the presence of excess dopamine and serotonin, showing that NO may be determined in the presence of these molecules. However, oxidation currents due to serotonin were found to decrease with increase in NO concentration. The CoPc-ME could also detect NO added to blood or its components, the oxidation currents for NO, however, decreased rapidly with time. The decrease in currents was slower in blood serum, followed by whole blood, with a faster decrease being observed in blood plasma.
- Full Text:
- Date Issued: 2001
- Authors: Vilakazi, Sibulelo Lea , Nyokong, Tebello
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/291629 , vital:56893 , xlink:href="https://doi.org/10.1016/S0022-0728(01)00583-6"
- Description: The catalytic activity of a carbon fiber microelectrode modified with cobalt phthalocyanine (CoPc-ME) for the detection of nitric oxide in the presence of possible interfering molecules (dopamine and serotonin) is examined. A linear plot is observed for the variation of the catalytic currents with NO concentration in the presence of excess dopamine and serotonin, showing that NO may be determined in the presence of these molecules. However, oxidation currents due to serotonin were found to decrease with increase in NO concentration. The CoPc-ME could also detect NO added to blood or its components, the oxidation currents for NO, however, decreased rapidly with time. The decrease in currents was slower in blood serum, followed by whole blood, with a faster decrease being observed in blood plasma.
- Full Text:
- Date Issued: 2001
Woodlands or wastelands: Examining the value of South Africa's woodlands paper
- Shackleton, Charlie M, Willis, C B, Scholes, Robert J
- Authors: Shackleton, Charlie M , Willis, C B , Scholes, Robert J
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182158 , vital:43805 , xlink:href="https://hdl.handle.net/10520/EJC33869"
- Description: The savanna woodlands are the largest biome in the country, constituting one-third of South Africa. They are also home to one-quarter of the population, with 70 % of the former homelands being in the savanna biome. Consequently, they have the potential to make a marked contribution to the national economy, both in the formal and informal sector. They are also valuable on a national scale in terms of the ecosystem services they provide, such as carbon storage, biodiversity and water yield. Until recently the real and potential values attached to South Africa's savannas have not been recognised in policy fora and government institutions. Recent policy changes, especially the National Forestry Action Programme and the National Forest Act, have attempted to remedy this situation. These policies have not filtered down to land owners and managers, nor have they resulted in a redirection of government resources. Thus, large areas remain subject to unsustainable use. It is necessary that the true value of woodlands be determined and acknowledged as a stimulus to government agencies, the private sector and local users to use this valuable resource sustainably.
- Full Text:
- Date Issued: 2001
- Authors: Shackleton, Charlie M , Willis, C B , Scholes, Robert J
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182158 , vital:43805 , xlink:href="https://hdl.handle.net/10520/EJC33869"
- Description: The savanna woodlands are the largest biome in the country, constituting one-third of South Africa. They are also home to one-quarter of the population, with 70 % of the former homelands being in the savanna biome. Consequently, they have the potential to make a marked contribution to the national economy, both in the formal and informal sector. They are also valuable on a national scale in terms of the ecosystem services they provide, such as carbon storage, biodiversity and water yield. Until recently the real and potential values attached to South Africa's savannas have not been recognised in policy fora and government institutions. Recent policy changes, especially the National Forestry Action Programme and the National Forest Act, have attempted to remedy this situation. These policies have not filtered down to land owners and managers, nor have they resulted in a redirection of government resources. Thus, large areas remain subject to unsustainable use. It is necessary that the true value of woodlands be determined and acknowledged as a stimulus to government agencies, the private sector and local users to use this valuable resource sustainably.
- Full Text:
- Date Issued: 2001
Working conditions agreement for SACCAWU employees
- SACCAWU
- Authors: SACCAWU
- Date: 2001
- Subjects: SACCAWU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/175924 , vital:42641
- Description: As a SACCAWU Staff Member it is important to know exactly what your Conditions of Service are hence this booklet. The Union believes in the principle of good and fair treatment of Staff and sees this as encouraging motivated and dedicated Officials. We have therefore tried to make Conditions as favourable as possible within the constraints of being a no-profit making organisation. In return, however the organisation does expect diligence, commitment and efficiency. Staff have the right before 1st March, every year to put forward proposals to* National Finance Committee in order to improve Working Conditions. Two Representatives elected from each Region will attend National Discussions/Engagements which shall put together a national mandate and elect Representatives to meet with NFC.
- Full Text:
- Date Issued: 2001
- Authors: SACCAWU
- Date: 2001
- Subjects: SACCAWU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/175924 , vital:42641
- Description: As a SACCAWU Staff Member it is important to know exactly what your Conditions of Service are hence this booklet. The Union believes in the principle of good and fair treatment of Staff and sees this as encouraging motivated and dedicated Officials. We have therefore tried to make Conditions as favourable as possible within the constraints of being a no-profit making organisation. In return, however the organisation does expect diligence, commitment and efficiency. Staff have the right before 1st March, every year to put forward proposals to* National Finance Committee in order to improve Working Conditions. Two Representatives elected from each Region will attend National Discussions/Engagements which shall put together a national mandate and elect Representatives to meet with NFC.
- Full Text:
- Date Issued: 2001
XML to facilitate management of multi-vendor networks
- Halse, Guy A, Wells, George C, Terzoli, Alfredo
- Authors: Halse, Guy A , Wells, George C , Terzoli, Alfredo
- Date: 2001
- Subjects: XML Network Management SNMP
- Language: English
- Type: Conference paper
- Identifier: vital:6602 , http://hdl.handle.net/10962/d1009322
- Description: Many standards aimed at managing networks currently exist, and yet networks remain notoriously difficult to maintain. Template-based management systems go a long way towards solving this problem. By developing an XML based language to describe network elements, as well as the topology of a network, we can create tools that are free from vendor specific idiosyncrasies, and are capable of managing both today’s networks and those of the future.
- Full Text:
- Date Issued: 2001
- Authors: Halse, Guy A , Wells, George C , Terzoli, Alfredo
- Date: 2001
- Subjects: XML Network Management SNMP
- Language: English
- Type: Conference paper
- Identifier: vital:6602 , http://hdl.handle.net/10962/d1009322
- Description: Many standards aimed at managing networks currently exist, and yet networks remain notoriously difficult to maintain. Template-based management systems go a long way towards solving this problem. By developing an XML based language to describe network elements, as well as the topology of a network, we can create tools that are free from vendor specific idiosyncrasies, and are capable of managing both today’s networks and those of the future.
- Full Text:
- Date Issued: 2001
Young women's memories of their experiences in adolescent relationships : a qualitative study
- Authors: Breetzke, Andrea Welsh
- Date: 2001
- Subjects: Teenage girls , Adolescent psychology , Teenagers , Parent and teenager , Teenage parents
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:690 , http://hdl.handle.net/10962/d1006366 , Teenage girls , Adolescent psychology , Teenagers , Parent and teenager , Teenage parents
- Description: Democratic Government in South Africa has brought with it changes in ideology and policy as well as a focus on a new area of concern. It has recognised the importance of young people. In May 1995 the Inter-Ministerial Committee for Youth at Risk (IMC) was established to re-organise the Child and Youth Care system in order increase its effectivity in coping with vulnerable youths. The IMC proposed a new framework for understanding and working with youth based on the principle of the Sioux parenting practices, called the Circle of Courage. Traditionally, helping professionals such as social workers use western theories, such as Erikson's Psychosocial Stage theory, to understand adolescents. Both of these theories and philosophies were not developed in South Africa and there is, therefore, cause for concern as to their relevance to the diverse and unique circumstances of this country. In this qualitative study, five young South African women attending a tertiary institution were asked to tell the stories of their adolescence with specific reference to their boy/girl relationships and factors influencing these relationships. The data was gathered in one or two semi-structured interviews. Data was analysed using Miles and Huberman's (1994) broad model using data reduction (through coding), data display (with the use of two context charts and a thematic conceptual matrix)and verification and conclusion drawing (through finding synergies and contrasts between the data and the two theories). This analysis was conducted with two specific aims. The first aim was to provide a thick description of one of the women's stories to show the complexity and diversity of her experience. Secondly, synergies and contrasts were sought between the women's stories and the two theories: Erikson's stage theory and the Circle of Courage. The analysis showed strong evidence that aspects from both these theories existed in the data and that to some degree both were relevant to the experiences of these five women.
- Full Text:
- Date Issued: 2001
- Authors: Breetzke, Andrea Welsh
- Date: 2001
- Subjects: Teenage girls , Adolescent psychology , Teenagers , Parent and teenager , Teenage parents
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:690 , http://hdl.handle.net/10962/d1006366 , Teenage girls , Adolescent psychology , Teenagers , Parent and teenager , Teenage parents
- Description: Democratic Government in South Africa has brought with it changes in ideology and policy as well as a focus on a new area of concern. It has recognised the importance of young people. In May 1995 the Inter-Ministerial Committee for Youth at Risk (IMC) was established to re-organise the Child and Youth Care system in order increase its effectivity in coping with vulnerable youths. The IMC proposed a new framework for understanding and working with youth based on the principle of the Sioux parenting practices, called the Circle of Courage. Traditionally, helping professionals such as social workers use western theories, such as Erikson's Psychosocial Stage theory, to understand adolescents. Both of these theories and philosophies were not developed in South Africa and there is, therefore, cause for concern as to their relevance to the diverse and unique circumstances of this country. In this qualitative study, five young South African women attending a tertiary institution were asked to tell the stories of their adolescence with specific reference to their boy/girl relationships and factors influencing these relationships. The data was gathered in one or two semi-structured interviews. Data was analysed using Miles and Huberman's (1994) broad model using data reduction (through coding), data display (with the use of two context charts and a thematic conceptual matrix)and verification and conclusion drawing (through finding synergies and contrasts between the data and the two theories). This analysis was conducted with two specific aims. The first aim was to provide a thick description of one of the women's stories to show the complexity and diversity of her experience. Secondly, synergies and contrasts were sought between the women's stories and the two theories: Erikson's stage theory and the Circle of Courage. The analysis showed strong evidence that aspects from both these theories existed in the data and that to some degree both were relevant to the experiences of these five women.
- Full Text:
- Date Issued: 2001