No description available.

Growing needs for precise manipulation in medical surgery, manufacturing automation and structural health monitoring have motivated development of high accuracy, bandwidth and cost-effective sensing systems. Among these is a class of multi-axis electromagnetic devices where embedded magnetic fields can be capitalized for compact position estimation eliminating unwanted friction, stiction and inertia arising from dedicated and separate sensing mechanisms. Using fields for position measurements, however, is a challenging 'inverse problem' since they are often modeled in the 'forward' sense and their inverse solutions are often highly non-linear and non-unique. A general method to design a multisensor system that capitalizes on the existing magnetic field in permanent magnet (PM) actuators is presented. This method takes advantage of the structural field symmetry and meticulous placement of sensors to discretize the motion range of a PM-based device into smaller magnetic field segments, thereby reducing the required characterization domain. Within these localized segments, unique field-position correspondence is induced using field measurements from a network of multiple-axis sensors. A direct mapping approach utilizing trained artificial neural networks to attain multi-DOF positional information from distributed field measurements is employed as an alternative to existing computationally intensive model based methods which are unsuitable for real-time control implementation. Validation and evaluation of this technique are performed through field simulations and experimental investigation on an electromagnetic spherical actuator. An inclinometer was used as a performance comparison and experimental results have corroborated the superior tracking ability of the field-based sensing system. While the immediate application is field-based orientation determination of an electromagnetic actuator, it is expected that the design method can be extended to develop other sensing systems that harnesses other scalar, vector and tensor fields.

In low-resource contexts, household-level point-of-use water treatment (POUWT) techniques are the final, and sometimes only, barrier against waterborne illnesses, and in these and other water-related applications, health risks can be quantified using one of two methods. Firstly, Escherichia coli (or other indicator organism) counts can be used to monitor water and determine adherence to a health-based limit (i.e. compliance monitoring). Secondly, E. coli can be used to conduct a quantitative microbial risk assessment (QMRA), indicating the level of protection conferred by a given POUWT device by spiking test water with E. coli to ascertain a reduction efficacy relative to that target organism, a process referred to as challenge testing, which is typically carried out in a laboratory context. Although both methods are well established, both have scope for improvement for effective field application in low-resource contexts. Regarding compliance monitoring, I assessed the performance of a new low-cost field kit for E. coli enumeration, which was designed by others. I also assessed the feasibility of re-using some disposable materials, in terms of sterility and mechanical wear. The use of the new low-cost field kit was successful during the fieldwork campaign; however, re-using disposable materials introduced a relatively high occurrence of false positive results during E. coli enumeration. Use of the new low-cost field kit can reduce financial barriers, thus enabling greater water quality testing coverage. Regarding challenge testing, the aim of this study was to adapt current protocols to assess the household performance (as opposed to laboratory performance) of POUWT techniques. I developed a conceptual framework to conduct Field Challenge Tests (FCT’s) on POUWT techniques, using a probiotic health supplement containing E. coli as the challenge organism. I successfully carried out a FCT in Malawi with limited resources, verifying FCT viability. Applications of such FCT’s include quality control practices for manufactured devices, guiding QMRA and recommendations by public health organizations regarding POU device selection, and assessing the impact of user training programmes regarding POUWT techniques. / Graduate

Cette recherche, menée en immersion sur le terrain, vise à rendre plus intelligible le mode projet dans le système de décision des organisations bureaucratiques. Ce sujet, manquant d’évidences tant conceptuelles qu’empiriques, a été analysé longitudinalement et en temps réel par le biais d’une étude de cas enchâssés, composée de cinq projets internes d’une même collectivité territoriale. Pour appréhender davantage la complexité de ce sujet, un cadre conceptuel a été spécifiquement développé sur la base d’une approche multidimensionnelle. Puis, différents dispositifs méthodologiques, oscillant de l’observation flottante jusqu’à la recherche-action, ont été mobilisés pour détecter ce qui relève du singulier ou de la répétition dans les pratiques. Au final, les résultats de cette thèse, largement révélés par l’exercice d’une réflexivité, suggèrent que l’analyse du mode projet dans le système de décision d’une organisation bureaucratique ne peut être menée sans l’usage du concept d’instanciation. Plus encore, au sein des bureaucraties publiques, les projets internes connaissent une instanciation incomplète, néfaste à leur efficience. / This research, performed on the field-based approach, aims to give a more intelligible view of the project mode in the decision-making system within bureaucratic organizations. As this subject lacked of both conceptual and empiric evidences, it was analyzed on a real-time and longitudinal basis by means of embedded case study, composed of five internal projects performed in a territorial community. To advance deeper with the complexity of the subject, a conceptual frame was specifically done on the basis of a multidimensional approach. Then, several methological tools, from floating observation to action-research, were mobilized in order to identify if the practices tackled are either originated in a singular or repetitive approach. Finally, this thesis results, highly revealed through the exercise of reflexivity, show us that the analysis of the mode project in decision-making system within a bureaucratic organization can’t be lead without using the concept of instantiation. Moreover, within the public bureaucracies, the internal projects suffer from an unachieved instantiation, undermining their efficiency.

No description available.

ABSTRACT DECISION TREE CLASSIFICATION OF MULTI-TEMPORAL IMAGES FOR FIELD-BASED CROP MAPPING Sencan, Se&ccedil / il M. Sc., Department of Geodetic and Geographic Information Technologies Supervisor: Assist. Prof. Dr. Mustafa T&uuml / rker August 2004, 125 pages A decision tree (DT) classification approach was used to identify summer (August) crop types in an agricultural area near Karacabey (Bursa), Turkey from multi-temporal images. For the analysis, Landsat 7 ETM+ images acquired in May, July, and August 2000 were used. In addition to the original bands, NDVI, PCA, and Tasselled Cap Transformation bands were also generated and included in the classification procedure. Initially, the images were classified on a per-pixel basis using the multi-temporal masking technique together with the DT approach. Then, the classified outputs were applied a field-based analysis and the class labels of the fields were directly entered into the Geographical Information System (GIS) database. The results were compared with the classified outputs of the three dates of imagery generated using a traditional maximum likelihood (ML) algorithm. It was observed that the proposed approach provided significantly higher overall accuracies for the May and August images, for which the number of classes were low. In May and July, the DT approach produced the classification accuracies of 91.10% and 66.15% while the ML classifier produced 84.38% and 63.55%, respectively. However, in August nearly the similar overall accuracies were obtained for the ML (70.82%) and DT (69.14%) approaches. It was also observed that the use of additional bands for the proposed technique improved the separability of the sugar beet, tomato, pea, pepper, and rice classes.

Xylophagous borers and termites that damage "timber-in-service" cause millions of dollars loss annually throughout mainland Australia. I developed field-based feeding assays with practical relevance to preventative action and remedial treatment of infestations of xylophagous insects in the built environment. Essential to this work is facilitating a high termite risk by maintaining an environment conducive to sustained foraging by termites. Feeding assays conducted in low termite risk areas are unduly prolonged, with inherently erratic termite feeding responses. I successfully developed feeding assays with a high termite risk. To establish whether a physical barrier, retrofitted as a sleeve, could prevent termites from damaging wooden poles, eighty poles were established within Beerburrum State Forest, south-east Queensland, Australia. Poles within sets were interconnected with buried timber to facilitate a high risk to Coptotermes acinaciformis (Froggatt). Mesh sleeves to a depth of 1.5m did not prevent termite damage to the poles. Hoop pine Araucaria cunninghamii Ait. ex D.Don dowels ("dip-sticks") were useful termite monitoring devices on the poles. The depth of foraging by termites has implications for the effectiveness of retrofitted physical and chemical barriers in general. Timber quantity and quality has a pivotal influence on the aggregation of large numbers of feeding termites necessary for baiting work and for producing efficacy data of relevance to the protection of timber-in-service from termites. Seasonal variation in termite foraging was examined. Both C. acinaciformis and Coptotermes lacteus (Froggatt) were more active feeding in summer than in autumn. In general, mass loss followed mean ambient temperature. Suppression of C. acinaciformis feeding responses relative to C. lacteus during summer, particularly during January, is thought to be due to excessive temperatures in the containers attached to infested trees. Termite foraging behaviour and responses to both varying masses of softwood timbers and varying exposure times were investigated. The rate of mass loss was independent of the number of test specimens and appeared linear. Colonies regulate the number of foragers directly according to the mass of susceptible timber available. This phenomenon was exploited throughout the remainder of the thesis. Of particular significance was the considerable intra- and inter-specific variation in susceptibility of softwoods to C. acinaciformis and Mastotermes darwiniensis Froggatt. The sapwoods tested were susceptible, but the heartwoods were generally resistant to damage by termites. These data confirm that termites are discriminating feeders, and some more so than others. A novel methodology, developed to maintain an environment conducive to sustained foraging by termites during field-testing, is presented. Consistency in timber acceptance and susceptibility to termites is considered to be important in determining the frequency of inspection and the success of bait systems. I evaluate the termiticidal activity of the bait toxicants hexaflumuron and chlorfluazuron for the management of the subterranean termite C. acinaciformis in the field. The Sentricon Colony Elimination System with Baitube-devices containing 0.1% and 1% mass/mass (m/m) hexaflumuron bait toxicant in dry wood flour (Recruit) was successful in eliminating field colonies of C. acinaciformis. Similarly, the Exterra Termite Interception and Baiting System with cellulose-acetate powder containing either 0.05% m/m or 0.25% m/m chlorfluazuron (Requiem) eliminated C. acinaciformis. Indicators (including "dip-sticks") used to monitor colony health were reliable. By using C. acinaciformis, which builds mounds (epigeous nests) in northern Australia, I was able to avoid the use of multiple mark-release schemes to verify the effects of the bait toxicant on the termite colonies. Problems with multiple mark-release schemes, used elsewhere in the world, are discussed. I continued the focus on bait quality and placement by evaluating termite responses to two aspects of treated stakes, their attractiveness and their susceptibility. Three experiments were undertaken near Townsville and at Beerburrum, with Coptotermes and Schedorhinotermes. Whilst there were no significant differences in the rate of location and foraging, with respect to treatments, differences in foraging, with respect to C. acinaciformis and Schedorhinotermes seclusus (Hill) were significant. Coptotermes acinaciformis displayed greater foraging site tenacity than S. seclusus at Beerburrum. Increased consumption of bait, due to the addition of a phagostimulant, needs to be observed in the field before an increase in the efficacy of baits in a termite management program can be claimed. In Australia, softwood timbers are extensively used in building construction and are generally highly susceptible to damage by termites. I focussed on field feeding assays to test efficacy of borate-treated softwoods against termites and to define "adequate" protection thresholds. Laboratory and field data reported in the literature were confusing with regard to what constitutes "adequate" protection thresholds. The confusion was compounded by differences in termite species, timber species used and test methodology. Laboratory data indicated a borate loading of 0.5% m/m boric acid equivalent (BAE) would cause > 90% termite mortality and restrict mass loss in test specimens to 5%. Field data generally suggested that borate loadings in excess of 0.5% m/m BAE were required. The main contribution of the work to increasing our understanding of management options for termites in the built environment was in resolving the confusion between laboratory and field data for borate wood-preservatives. These apparently conflicting results were explained by the presence or absence of untreated feeder material in the test environment. In the absence of untreated feeder material, retention of 0.5% BAE provides adequate protection from Coptotermes sp., whereas in the presence of untreated feeder material, increased retentions are required. Furthermore, the retentions required increase with increased amounts of susceptible material. Some termites, Nasutitermes sp. and M. darwiniensis, for example, are borate-tolerant and borate wood-preservatives are not a viable management option. The lack of uniform standards for termite-test methodology and assessment criteria for efficacy across the world is recognized as a difficulty with research into the performance of wood preservatives with termites. The many variables in laboratory and field assays make "prescriptive" standards difficult to recommend. The use of "performance" standards to define efficacy criteria ("adequate" protection) is discussed. Whilst the majority of the work involves subterranean termites ("termites"), I examine the question of how to define a hardwood timber species as "not susceptible" to lyctine beetle damage. Aspects of the biology, behaviour and management of Lyctus brunneus (Stephens) are reviewed and a novel field sampling and testing protocol to establish lyctine susceptibility of timber species is presented. A sound understanding of the biology and behaviour of xylophagous insects in the field is essential to ensure that management options implemented in the built environment have a strong ecological basis. The success of this study in achieving stated aims, the need for further work and the implications for test methodologies in the field with practical relevance to infestations of xylophagous insects in the built environment are discussed.

Xylophagous borers and termites that damage "timber-in-service" cause millions of dollars loss annually throughout mainland Australia. I developed field-based feeding assays with practical relevance to preventative action and remedial treatment of infestations of xylophagous insects in the built environment. Essential to this work is facilitating a high termite risk by maintaining an environment conducive to sustained foraging by termites. Feeding assays conducted in low termite risk areas are unduly prolonged, with inherently erratic termite feeding responses. I successfully developed feeding assays with a high termite risk. To establish whether a physical barrier, retrofitted as a sleeve, could prevent termites from damaging wooden poles, eighty poles were established within Beerburrum State Forest, south-east Queensland, Australia. Poles within sets were interconnected with buried timber to facilitate a high risk to Coptotermes acinaciformis (Froggatt). Mesh sleeves to a depth of 1.5m did not prevent termite damage to the poles. Hoop pine Araucaria cunninghamii Ait. ex D.Don dowels ("dip-sticks") were useful termite monitoring devices on the poles. The depth of foraging by termites has implications for the effectiveness of retrofitted physical and chemical barriers in general. Timber quantity and quality has a pivotal influence on the aggregation of large numbers of feeding termites necessary for baiting work and for producing efficacy data of relevance to the protection of timber-in-service from termites. Seasonal variation in termite foraging was examined. Both C. acinaciformis and Coptotermes lacteus (Froggatt) were more active feeding in summer than in autumn. In general, mass loss followed mean ambient temperature. Suppression of C. acinaciformis feeding responses relative to C. lacteus during summer, particularly during January, is thought to be due to excessive temperatures in the containers attached to infested trees. Termite foraging behaviour and responses to both varying masses of softwood timbers and varying exposure times were investigated. The rate of mass loss was independent of the number of test specimens and appeared linear. Colonies regulate the number of foragers directly according to the mass of susceptible timber available. This phenomenon was exploited throughout the remainder of the thesis. Of particular significance was the considerable intra- and inter-specific variation in susceptibility of softwoods to C. acinaciformis and Mastotermes darwiniensis Froggatt. The sapwoods tested were susceptible, but the heartwoods were generally resistant to damage by termites. These data confirm that termites are discriminating feeders, and some more so than others. A novel methodology, developed to maintain an environment conducive to sustained foraging by termites during field-testing, is presented. Consistency in timber acceptance and susceptibility to termites is considered to be important in determining the frequency of inspection and the success of bait systems. I evaluate the termiticidal activity of the bait toxicants hexaflumuron and chlorfluazuron for the management of the subterranean termite C. acinaciformis in the field. The Sentricon Colony Elimination System with Baitube-devices containing 0.1% and 1% mass/mass (m/m) hexaflumuron bait toxicant in dry wood flour (Recruit) was successful in eliminating field colonies of C. acinaciformis. Similarly, the Exterra Termite Interception and Baiting System with cellulose-acetate powder containing either 0.05% m/m or 0.25% m/m chlorfluazuron (Requiem) eliminated C. acinaciformis. Indicators (including "dip-sticks") used to monitor colony health were reliable. By using C. acinaciformis, which builds mounds (epigeous nests) in northern Australia, I was able to avoid the use of multiple mark-release schemes to verify the effects of the bait toxicant on the termite colonies. Problems with multiple mark-release schemes, used elsewhere in the world, are discussed. I continued the focus on bait quality and placement by evaluating termite responses to two aspects of treated stakes, their attractiveness and their susceptibility. Three experiments were undertaken near Townsville and at Beerburrum, with Coptotermes and Schedorhinotermes. Whilst there were no significant differences in the rate of location and foraging, with respect to treatments, differences in foraging, with respect to C. acinaciformis and Schedorhinotermes seclusus (Hill) were significant. Coptotermes acinaciformis displayed greater foraging site tenacity than S. seclusus at Beerburrum. Increased consumption of bait, due to the addition of a phagostimulant, needs to be observed in the field before an increase in the efficacy of baits in a termite management program can be claimed. In Australia, softwood timbers are extensively used in building construction and are generally highly susceptible to damage by termites. I focussed on field feeding assays to test efficacy of borate-treated softwoods against termites and to define "adequate" protection thresholds. Laboratory and field data reported in the literature were confusing with regard to what constitutes "adequate" protection thresholds. The confusion was compounded by differences in termite species, timber species used and test methodology. Laboratory data indicated a borate loading of 0.5% m/m boric acid equivalent (BAE) would cause > 90% termite mortality and restrict mass loss in test specimens to 5%. Field data generally suggested that borate loadings in excess of 0.5% m/m BAE were required. The main contribution of the work to increasing our understanding of management options for termites in the built environment was in resolving the confusion between laboratory and field data for borate wood-preservatives. These apparently conflicting results were explained by the presence or absence of untreated feeder material in the test environment. In the absence of untreated feeder material, retention of 0.5% BAE provides adequate protection from Coptotermes sp., whereas in the presence of untreated feeder material, increased retentions are required. Furthermore, the retentions required increase with increased amounts of susceptible material. Some termites, Nasutitermes sp. and M. darwiniensis, for example, are borate-tolerant and borate wood-preservatives are not a viable management option. The lack of uniform standards for termite-test methodology and assessment criteria for efficacy across the world is recognized as a difficulty with research into the performance of wood preservatives with termites. The many variables in laboratory and field assays make "prescriptive" standards difficult to recommend. The use of "performance" standards to define efficacy criteria ("adequate" protection) is discussed. Whilst the majority of the work involves subterranean termites ("termites"), I examine the question of how to define a hardwood timber species as "not susceptible" to lyctine beetle damage. Aspects of the biology, behaviour and management of Lyctus brunneus (Stephens) are reviewed and a novel field sampling and testing protocol to establish lyctine susceptibility of timber species is presented. A sound understanding of the biology and behaviour of xylophagous insects in the field is essential to ensure that management options implemented in the built environment have a strong ecological basis. The success of this study in achieving stated aims, the need for further work and the implications for test methodologies in the field with practical relevance to infestations of xylophagous insects in the built environment are discussed.

Xylophagous borers and termites that damage "timber-in-service" cause millions of dollars loss annually throughout mainland Australia. I developed field-based feeding assays with practical relevance to preventative action and remedial treatment of infestations of xylophagous insects in the built environment. Essential to this work is facilitating a high termite risk by maintaining an environment conducive to sustained foraging by termites. Feeding assays conducted in low termite risk areas are unduly prolonged, with inherently erratic termite feeding responses. I successfully developed feeding assays with a high termite risk. To establish whether a physical barrier, retrofitted as a sleeve, could prevent termites from damaging wooden poles, eighty poles were established within Beerburrum State Forest, south-east Queensland, Australia. Poles within sets were interconnected with buried timber to facilitate a high risk to Coptotermes acinaciformis (Froggatt). Mesh sleeves to a depth of 1.5m did not prevent termite damage to the poles. Hoop pine Araucaria cunninghamii Ait. ex D.Don dowels ("dip-sticks") were useful termite monitoring devices on the poles. The depth of foraging by termites has implications for the effectiveness of retrofitted physical and chemical barriers in general. Timber quantity and quality has a pivotal influence on the aggregation of large numbers of feeding termites necessary for baiting work and for producing efficacy data of relevance to the protection of timber-in-service from termites. Seasonal variation in termite foraging was examined. Both C. acinaciformis and Coptotermes lacteus (Froggatt) were more active feeding in summer than in autumn. In general, mass loss followed mean ambient temperature. Suppression of C. acinaciformis feeding responses relative to C. lacteus during summer, particularly during January, is thought to be due to excessive temperatures in the containers attached to infested trees. Termite foraging behaviour and responses to both varying masses of softwood timbers and varying exposure times were investigated. The rate of mass loss was independent of the number of test specimens and appeared linear. Colonies regulate the number of foragers directly according to the mass of susceptible timber available. This phenomenon was exploited throughout the remainder of the thesis. Of particular significance was the considerable intra- and inter-specific variation in susceptibility of softwoods to C. acinaciformis and Mastotermes darwiniensis Froggatt. The sapwoods tested were susceptible, but the heartwoods were generally resistant to damage by termites. These data confirm that termites are discriminating feeders, and some more so than others. A novel methodology, developed to maintain an environment conducive to sustained foraging by termites during field-testing, is presented. Consistency in timber acceptance and susceptibility to termites is considered to be important in determining the frequency of inspection and the success of bait systems. I evaluate the termiticidal activity of the bait toxicants hexaflumuron and chlorfluazuron for the management of the subterranean termite C. acinaciformis in the field. The Sentricon Colony Elimination System with Baitube-devices containing 0.1% and 1% mass/mass (m/m) hexaflumuron bait toxicant in dry wood flour (Recruit) was successful in eliminating field colonies of C. acinaciformis. Similarly, the Exterra Termite Interception and Baiting System with cellulose-acetate powder containing either 0.05% m/m or 0.25% m/m chlorfluazuron (Requiem) eliminated C. acinaciformis. Indicators (including "dip-sticks") used to monitor colony health were reliable. By using C. acinaciformis, which builds mounds (epigeous nests) in northern Australia, I was able to avoid the use of multiple mark-release schemes to verify the effects of the bait toxicant on the termite colonies. Problems with multiple mark-release schemes, used elsewhere in the world, are discussed. I continued the focus on bait quality and placement by evaluating termite responses to two aspects of treated stakes, their attractiveness and their susceptibility. Three experiments were undertaken near Townsville and at Beerburrum, with Coptotermes and Schedorhinotermes. Whilst there were no significant differences in the rate of location and foraging, with respect to treatments, differences in foraging, with respect to C. acinaciformis and Schedorhinotermes seclusus (Hill) were significant. Coptotermes acinaciformis displayed greater foraging site tenacity than S. seclusus at Beerburrum. Increased consumption of bait, due to the addition of a phagostimulant, needs to be observed in the field before an increase in the efficacy of baits in a termite management program can be claimed. In Australia, softwood timbers are extensively used in building construction and are generally highly susceptible to damage by termites. I focussed on field feeding assays to test efficacy of borate-treated softwoods against termites and to define "adequate" protection thresholds. Laboratory and field data reported in the literature were confusing with regard to what constitutes "adequate" protection thresholds. The confusion was compounded by differences in termite species, timber species used and test methodology. Laboratory data indicated a borate loading of 0.5% m/m boric acid equivalent (BAE) would cause > 90% termite mortality and restrict mass loss in test specimens to 5%. Field data generally suggested that borate loadings in excess of 0.5% m/m BAE were required. The main contribution of the work to increasing our understanding of management options for termites in the built environment was in resolving the confusion between laboratory and field data for borate wood-preservatives. These apparently conflicting results were explained by the presence or absence of untreated feeder material in the test environment. In the absence of untreated feeder material, retention of 0.5% BAE provides adequate protection from Coptotermes sp., whereas in the presence of untreated feeder material, increased retentions are required. Furthermore, the retentions required increase with increased amounts of susceptible material. Some termites, Nasutitermes sp. and M. darwiniensis, for example, are borate-tolerant and borate wood-preservatives are not a viable management option. The lack of uniform standards for termite-test methodology and assessment criteria for efficacy across the world is recognized as a difficulty with research into the performance of wood preservatives with termites. The many variables in laboratory and field assays make "prescriptive" standards difficult to recommend. The use of "performance" standards to define efficacy criteria ("adequate" protection) is discussed. Whilst the majority of the work involves subterranean termites ("termites"), I examine the question of how to define a hardwood timber species as "not susceptible" to lyctine beetle damage. Aspects of the biology, behaviour and management of Lyctus brunneus (Stephens) are reviewed and a novel field sampling and testing protocol to establish lyctine susceptibility of timber species is presented. A sound understanding of the biology and behaviour of xylophagous insects in the field is essential to ensure that management options implemented in the built environment have a strong ecological basis. The success of this study in achieving stated aims, the need for further work and the implications for test methodologies in the field with practical relevance to infestations of xylophagous insects in the built environment are discussed.

Xylophagous borers and termites that damage "timber-in-service" cause millions of dollars loss annually throughout mainland Australia. I developed field-based feeding assays with practical relevance to preventative action and remedial treatment of infestations of xylophagous insects in the built environment. Essential to this work is facilitating a high termite risk by maintaining an environment conducive to sustained foraging by termites. Feeding assays conducted in low termite risk areas are unduly prolonged, with inherently erratic termite feeding responses. I successfully developed feeding assays with a high termite risk. To establish whether a physical barrier, retrofitted as a sleeve, could prevent termites from damaging wooden poles, eighty poles were established within Beerburrum State Forest, south-east Queensland, Australia. Poles within sets were interconnected with buried timber to facilitate a high risk to Coptotermes acinaciformis (Froggatt). Mesh sleeves to a depth of 1.5m did not prevent termite damage to the poles. Hoop pine Araucaria cunninghamii Ait. ex D.Don dowels ("dip-sticks") were useful termite monitoring devices on the poles. The depth of foraging by termites has implications for the effectiveness of retrofitted physical and chemical barriers in general. Timber quantity and quality has a pivotal influence on the aggregation of large numbers of feeding termites necessary for baiting work and for producing efficacy data of relevance to the protection of timber-in-service from termites. Seasonal variation in termite foraging was examined. Both C. acinaciformis and Coptotermes lacteus (Froggatt) were more active feeding in summer than in autumn. In general, mass loss followed mean ambient temperature. Suppression of C. acinaciformis feeding responses relative to C. lacteus during summer, particularly during January, is thought to be due to excessive temperatures in the containers attached to infested trees. Termite foraging behaviour and responses to both varying masses of softwood timbers and varying exposure times were investigated. The rate of mass loss was independent of the number of test specimens and appeared linear. Colonies regulate the number of foragers directly according to the mass of susceptible timber available. This phenomenon was exploited throughout the remainder of the thesis. Of particular significance was the considerable intra- and inter-specific variation in susceptibility of softwoods to C. acinaciformis and Mastotermes darwiniensis Froggatt. The sapwoods tested were susceptible, but the heartwoods were generally resistant to damage by termites. These data confirm that termites are discriminating feeders, and some more so than others. A novel methodology, developed to maintain an environment conducive to sustained foraging by termites during field-testing, is presented. Consistency in timber acceptance and susceptibility to termites is considered to be important in determining the frequency of inspection and the success of bait systems. I evaluate the termiticidal activity of the bait toxicants hexaflumuron and chlorfluazuron for the management of the subterranean termite C. acinaciformis in the field. The Sentricon Colony Elimination System with Baitube-devices containing 0.1% and 1% mass/mass (m/m) hexaflumuron bait toxicant in dry wood flour (Recruit) was successful in eliminating field colonies of C. acinaciformis. Similarly, the Exterra Termite Interception and Baiting System with cellulose-acetate powder containing either 0.05% m/m or 0.25% m/m chlorfluazuron (Requiem) eliminated C. acinaciformis. Indicators (including "dip-sticks") used to monitor colony health were reliable. By using C. acinaciformis, which builds mounds (epigeous nests) in northern Australia, I was able to avoid the use of multiple mark-release schemes to verify the effects of the bait toxicant on the termite colonies. Problems with multiple mark-release schemes, used elsewhere in the world, are discussed. I continued the focus on bait quality and placement by evaluating termite responses to two aspects of treated stakes, their attractiveness and their susceptibility. Three experiments were undertaken near Townsville and at Beerburrum, with Coptotermes and Schedorhinotermes. Whilst there were no significant differences in the rate of location and foraging, with respect to treatments, differences in foraging, with respect to C. acinaciformis and Schedorhinotermes seclusus (Hill) were significant. Coptotermes acinaciformis displayed greater foraging site tenacity than S. seclusus at Beerburrum. Increased consumption of bait, due to the addition of a phagostimulant, needs to be observed in the field before an increase in the efficacy of baits in a termite management program can be claimed. In Australia, softwood timbers are extensively used in building construction and are generally highly susceptible to damage by termites. I focussed on field feeding assays to test efficacy of borate-treated softwoods against termites and to define "adequate" protection thresholds. Laboratory and field data reported in the literature were confusing with regard to what constitutes "adequate" protection thresholds. The confusion was compounded by differences in termite species, timber species used and test methodology. Laboratory data indicated a borate loading of 0.5% m/m boric acid equivalent (BAE) would cause > 90% termite mortality and restrict mass loss in test specimens to 5%. Field data generally suggested that borate loadings in excess of 0.5% m/m BAE were required. The main contribution of the work to increasing our understanding of management options for termites in the built environment was in resolving the confusion between laboratory and field data for borate wood-preservatives. These apparently conflicting results were explained by the presence or absence of untreated feeder material in the test environment. In the absence of untreated feeder material, retention of 0.5% BAE provides adequate protection from Coptotermes sp., whereas in the presence of untreated feeder material, increased retentions are required. Furthermore, the retentions required increase with increased amounts of susceptible material. Some termites, Nasutitermes sp. and M. darwiniensis, for example, are borate-tolerant and borate wood-preservatives are not a viable management option. The lack of uniform standards for termite-test methodology and assessment criteria for efficacy across the world is recognized as a difficulty with research into the performance of wood preservatives with termites. The many variables in laboratory and field assays make "prescriptive" standards difficult to recommend. The use of "performance" standards to define efficacy criteria ("adequate" protection) is discussed. Whilst the majority of the work involves subterranean termites ("termites"), I examine the question of how to define a hardwood timber species as "not susceptible" to lyctine beetle damage. Aspects of the biology, behaviour and management of Lyctus brunneus (Stephens) are reviewed and a novel field sampling and testing protocol to establish lyctine susceptibility of timber species is presented. A sound understanding of the biology and behaviour of xylophagous insects in the field is essential to ensure that management options implemented in the built environment have a strong ecological basis. The success of this study in achieving stated aims, the need for further work and the implications for test methodologies in the field with practical relevance to infestations of xylophagous insects in the built environment are discussed.