A bi-directional SOAP/SMS gateway service
- Halse, Guy A, Terzoli, Alfredo, Wells, George C
- Authors: Halse, Guy A , Terzoli, Alfredo , Wells, George C
- Date: 2002
- Subjects: Broadband 2 SATNAC 2002
- Language: English
- Type: Conference paper
- Identifier: vital:6600 , http://hdl.handle.net/10962/d1008293
- Description: Many applications need the ability to do real-time notification when events occur. Often the people who need to be kept aware of events are in a remote location. This paper looks at a bi-directional gateway between networked computers and the GSM short message service. The gateway is implemented as a web service, and uses the Simple Object Access Protocol to facilitate data communication. The service interacts with a database in order to facilitate retrieval of sent or received messages, as well as provide accounting abilities. It is intended as a practical proof-of-concept application demonstrating some ofdemonstrating some of the capabilities of the Simple Object Access Protocol.
- Full Text:
- Date Issued: 2002
- Authors: Halse, Guy A , Terzoli, Alfredo , Wells, George C
- Date: 2002
- Subjects: Broadband 2 SATNAC 2002
- Language: English
- Type: Conference paper
- Identifier: vital:6600 , http://hdl.handle.net/10962/d1008293
- Description: Many applications need the ability to do real-time notification when events occur. Often the people who need to be kept aware of events are in a remote location. This paper looks at a bi-directional gateway between networked computers and the GSM short message service. The gateway is implemented as a web service, and uses the Simple Object Access Protocol to facilitate data communication. The service interacts with a database in order to facilitate retrieval of sent or received messages, as well as provide accounting abilities. It is intended as a practical proof-of-concept application demonstrating some ofdemonstrating some of the capabilities of the Simple Object Access Protocol.
- Full Text:
- Date Issued: 2002
Accelerated sludge solubilisation under sulphate reducing conditions: the effect of hydrolytic enzymes on sludge floc size distribution and EPS composition
- Akhurst, P, Rose, Peter D, Whiteley, Chris G, Pletschke, Brett I
- Authors: Akhurst, P , Rose, Peter D , Whiteley, Chris G , Pletschke, Brett I
- Date: 2002
- Language: English
- Type: Conference paper
- Identifier: vital:6455 , http://hdl.handle.net/10962/d1010430
- Description: Extracellular polymeric substances (EPS) are the construction materials for microbial aggregates such as biofilms, flocs and sludge, and greatly contribute to the structural integrity of sludge flocs in wastewater treatment processes. The loss of integrity of the sewage sludge floc is believed to be due to enhanced hydrolysis of important structural components such as lignin, protein and cellulose in the sludge floc matrix. The mechanism of enhanced sludge floc fracture, due to the action of enzymes hydrolysing these structural components, remains a key element in our understanding of how the floc integrity in systems utilising a sulphate reducing system is compromised. A range of relatively non-specific exogenous enzymes (ß-glucosidase, cellulase, proteases: trypsin, pronase E and chymotrypsin) were added to a sulphidogenic bioreactor- (containing both sulphate reducing bacteria (SRB) and a methanogenic bacterial system) and a (control) methanogenic bioreactor sample, and the effect of these enzymes on sludge floc size (diameter) distribution and EPS composition was investigated. Sludge samples from the bioreactors were examined under bright field and differential interference contrast light microscopy. Proteolytic and glucohydrolytic activity of the enzymes were monitored using standard enzyme assaying techniques, and Bradford, Somogyi-Nelson, and total carbohydrate assays were performed to establish the composition of the EPS (after extraction with 3% (v/v) glutaraldehyde and Sephacryl S-400 size exclusion chromatography). Sludge flocs present in the sulphidogenic environment of the sulphidogenic bioreactor were found to have smaller diameters than their counterparts present in the methanogenic bioreactor. The addition of hydrolytic (i.e. proteolytic and glycohydrolytic) enzymes resulted in an increased rate of matrix hydrolysis, leading to increased rates of floc fracture and deflocculation. The presence of ß-glucosidase, cellulase, and proteases naturally residing within the sludge floc was confirmed. We propose that the addition of commercially available enzymes may be prohibitively costly on a large scale, and that the activity of the enzymes naturally residing within the floc matrix be optimised or enhanced. As the bulk of the EPS was shown to be composed of mainly polysaccharides, we propose that by increasing the activity of the naturally occurring ß-glucosidases residing within the floc matrix, the process of deflocculation may be enhanced. As sulphide has been shown to increase the activity of this very important key enzyme, we propose that this is one of the contributing factors why sludge solubilisation is accelerated under sulphate reducing conditions.
- Full Text:
- Date Issued: 2002
- Authors: Akhurst, P , Rose, Peter D , Whiteley, Chris G , Pletschke, Brett I
- Date: 2002
- Language: English
- Type: Conference paper
- Identifier: vital:6455 , http://hdl.handle.net/10962/d1010430
- Description: Extracellular polymeric substances (EPS) are the construction materials for microbial aggregates such as biofilms, flocs and sludge, and greatly contribute to the structural integrity of sludge flocs in wastewater treatment processes. The loss of integrity of the sewage sludge floc is believed to be due to enhanced hydrolysis of important structural components such as lignin, protein and cellulose in the sludge floc matrix. The mechanism of enhanced sludge floc fracture, due to the action of enzymes hydrolysing these structural components, remains a key element in our understanding of how the floc integrity in systems utilising a sulphate reducing system is compromised. A range of relatively non-specific exogenous enzymes (ß-glucosidase, cellulase, proteases: trypsin, pronase E and chymotrypsin) were added to a sulphidogenic bioreactor- (containing both sulphate reducing bacteria (SRB) and a methanogenic bacterial system) and a (control) methanogenic bioreactor sample, and the effect of these enzymes on sludge floc size (diameter) distribution and EPS composition was investigated. Sludge samples from the bioreactors were examined under bright field and differential interference contrast light microscopy. Proteolytic and glucohydrolytic activity of the enzymes were monitored using standard enzyme assaying techniques, and Bradford, Somogyi-Nelson, and total carbohydrate assays were performed to establish the composition of the EPS (after extraction with 3% (v/v) glutaraldehyde and Sephacryl S-400 size exclusion chromatography). Sludge flocs present in the sulphidogenic environment of the sulphidogenic bioreactor were found to have smaller diameters than their counterparts present in the methanogenic bioreactor. The addition of hydrolytic (i.e. proteolytic and glycohydrolytic) enzymes resulted in an increased rate of matrix hydrolysis, leading to increased rates of floc fracture and deflocculation. The presence of ß-glucosidase, cellulase, and proteases naturally residing within the sludge floc was confirmed. We propose that the addition of commercially available enzymes may be prohibitively costly on a large scale, and that the activity of the enzymes naturally residing within the floc matrix be optimised or enhanced. As the bulk of the EPS was shown to be composed of mainly polysaccharides, we propose that by increasing the activity of the naturally occurring ß-glucosidases residing within the floc matrix, the process of deflocculation may be enhanced. As sulphide has been shown to increase the activity of this very important key enzyme, we propose that this is one of the contributing factors why sludge solubilisation is accelerated under sulphate reducing conditions.
- Full Text:
- Date Issued: 2002
Open source in South African schools : two case studies
- Halse, Guy A, Terzoli, Alfredo
- Authors: Halse, Guy A , Terzoli, Alfredo
- Date: 2002
- Subjects: Open source
- Language: English
- Type: Conference paper
- Identifier: vital:6601 , http://hdl.handle.net/10962/d1009321
- Description: One of the major problems facing schools in South Africa is the difficulty in obtaining modern, up-to-date computer facilities. This paper looks at the use of open source solutions in two government schools in South Africa to demonstrate that it is possible for schools to utilise almost any existing computer to provide effective network solutions.
- Full Text:
- Date Issued: 2002
- Authors: Halse, Guy A , Terzoli, Alfredo
- Date: 2002
- Subjects: Open source
- Language: English
- Type: Conference paper
- Identifier: vital:6601 , http://hdl.handle.net/10962/d1009321
- Description: One of the major problems facing schools in South Africa is the difficulty in obtaining modern, up-to-date computer facilities. This paper looks at the use of open source solutions in two government schools in South Africa to demonstrate that it is possible for schools to utilise almost any existing computer to provide effective network solutions.
- Full Text:
- Date Issued: 2002
The land question in South Africa, Zimbabwe and Kenya: a geographical perspective on resource endowment
- Fox, Roddy C, Rowntree, Kate M
- Authors: Fox, Roddy C , Rowntree, Kate M
- Date: 2002
- Language: English
- Type: Conference paper
- Identifier: vital:6664 , http://hdl.handle.net/10962/d1006671
- Description: In sharp contrast to the debates concerning land policy, land tenure and sustainable resource management in South Africa is any input concerning the geographical distribution of land productivity. This paper attempts to redress this imbalance by providing an empirical investigation of land potential in South Africa. In this way we intend to provide the crucial context for policy and academic studies of the land issue in South Africa. Furthermore, we will undertake our study in such a way that comparison can be made to Zimbabwe and Kenya where the land issue has been such a critical component of the post-colonial development process. Theoretically our work is contextualised within the debates surrounding the importance of geographical endowments, institutions and policies in the development process.
- Full Text:
- Date Issued: 2002
- Authors: Fox, Roddy C , Rowntree, Kate M
- Date: 2002
- Language: English
- Type: Conference paper
- Identifier: vital:6664 , http://hdl.handle.net/10962/d1006671
- Description: In sharp contrast to the debates concerning land policy, land tenure and sustainable resource management in South Africa is any input concerning the geographical distribution of land productivity. This paper attempts to redress this imbalance by providing an empirical investigation of land potential in South Africa. In this way we intend to provide the crucial context for policy and academic studies of the land issue in South Africa. Furthermore, we will undertake our study in such a way that comparison can be made to Zimbabwe and Kenya where the land issue has been such a critical component of the post-colonial development process. Theoretically our work is contextualised within the debates surrounding the importance of geographical endowments, institutions and policies in the development process.
- Full Text:
- Date Issued: 2002
- «
- ‹
- 1
- ›
- »