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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

A Generic Simulation-based Perioperative Decision Support Tool for Tactical Decision

Sniekers, Daphne 13 August 2013 (has links)
In Canada and around the world, there has been an increased focus on the efficiency, cost and access to health care services. One area of particular focus is surgical procedures, often with government funding and policies focused on reducing wait times through pay for performance and volume target initiatives. In Ontario, an expert panel was assembled to evaluate the current state of surgical processes and provide recommendations to improve access, efficiency and quality. This thesis addresses the panel's recommendation for a simulation-based decision tool to help hospitals inform decisions that can lead to improved access and efficiency. A generalised, simulation based perioperative decision tool is presented that can be used to test a variety of tactical decisions. The generic model has been applied to six hospitals of varying sizes, ranging from large academic centres to small rural community hospitals. The model remains in use at some of the hospitals to regularly inform decisions. The model is also being applied to additional hospital sites. During application of the generic model, challenges in design decisions and validation were encountered. As a result, a series of principles are proposed to guide future generic modelling design and achieving user acceptance. These principles add to the generic simulation modelling and healthcare modelling research fields by laying some groundwork for a formalised approach to designing effective generic simulation models and achieving confidence in results. Finally, the research demonstrates two uses of the generic model: as decision tool and as a demonstrative tool. As a decision tool the model is used to compare numerous potential tactical decision options under consideration. As a demonstrative tool, the model is used to quantify the effect of poor practices on hospital performance. The design of the generic model only considers efficient processes and best practices. When model results are compared to historical performance, decision makers are able to quantify the effect of existing poor practices on their performance and decision making. The tool enables users to base their tactical level decisions on the assumption that good practices and procedures are followed.
232

A Generic Simulation-based Perioperative Decision Support Tool for Tactical Decision

Sniekers, Daphne 13 August 2013 (has links)
In Canada and around the world, there has been an increased focus on the efficiency, cost and access to health care services. One area of particular focus is surgical procedures, often with government funding and policies focused on reducing wait times through pay for performance and volume target initiatives. In Ontario, an expert panel was assembled to evaluate the current state of surgical processes and provide recommendations to improve access, efficiency and quality. This thesis addresses the panel's recommendation for a simulation-based decision tool to help hospitals inform decisions that can lead to improved access and efficiency. A generalised, simulation based perioperative decision tool is presented that can be used to test a variety of tactical decisions. The generic model has been applied to six hospitals of varying sizes, ranging from large academic centres to small rural community hospitals. The model remains in use at some of the hospitals to regularly inform decisions. The model is also being applied to additional hospital sites. During application of the generic model, challenges in design decisions and validation were encountered. As a result, a series of principles are proposed to guide future generic modelling design and achieving user acceptance. These principles add to the generic simulation modelling and healthcare modelling research fields by laying some groundwork for a formalised approach to designing effective generic simulation models and achieving confidence in results. Finally, the research demonstrates two uses of the generic model: as decision tool and as a demonstrative tool. As a decision tool the model is used to compare numerous potential tactical decision options under consideration. As a demonstrative tool, the model is used to quantify the effect of poor practices on hospital performance. The design of the generic model only considers efficient processes and best practices. When model results are compared to historical performance, decision makers are able to quantify the effect of existing poor practices on their performance and decision making. The tool enables users to base their tactical level decisions on the assumption that good practices and procedures are followed.
233

An aquacultural development decision support system (ADDSS)

El-Gayar, Omar F January 1995 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 1995. / Includes bibliographical references (leaves 201-208). / Microfiche. / xv, 208 leaves, bound ill., col. maps 29 cm
234

Decision support system for assessing rice yield losses from annual flooding in Bangladesh

Hussain, Sk. Ghulam January 1995 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 1995. / Includes bibliographical references (leaves 132-137). / Microfiche. / xviii, 137 leaves, bound maps (some col.) 29 cm
235

Design and implementation of a heuristic-based decision support system for nurse scheduling

Sitompul, Darwin 16 October 1991 (has links)
A decision support system (DSS) for nurse scheduling in hospitals is developed and implemented on microcomputer. The system includes algorithms and databases for developing weekly work and shift patterns and combining these into working schedules for nurses for a specified time horizon, and interface modules for the user to interact with the system. The system combines heuristic modeling with decision analysis concepts to generate nurse schedules. A heuristic best-first search technique is used in implementing pattern generation and screening process to satisfy both nurses and hospital's objectives. Emphasis in the design of the DSS has been on computational efficiency and user acceptability. The system is flexible so that it can be implemented in different hospital environments, and incorporates a wide range of hospital and nurses' objectives. / Graduation date: 1992
236

Situation awareness measures in the land force /

French, Han Tin. Unknown Date (has links)
In the military domain, situation awareness (SA) is an important concept. The precise definition is elusive - generally it is accepted to mean 'knowing what is going on'. The presumption is that in battles, all combat personnel must have SA, without which they may face defeat or make serious mistakes with potentially dire consequences. The dynamic environment in which they operate is far from favourable for gaining and maintaining SA. Commanders and soldiers are under pressure to make decisions even though the situation is unclear. / The goal of the research project reported in this thesis is to adapt an existing measure of SA for use in the land force domain, and to investigate the validity of the measure. An SA metric provides a powerful tool in SA research. It has the capacity to provide rigour in studies examining the impact of technology insertion on SA. / SAGAT (Situation Awareness Global Assessment Technique)*, [Endsley, M. R. (1995). Measurement of Situation Awareness in Dynamic Systems. Human Factors, 37 (1), 65-84.] was developed to provide objective measures of SA for computer simulation studies in the aviation domain. In order to apply SAGAT in the field environment in the land domain, the technique had to be modified. This resulted in a new method called the Direct Questioning Technique (DQT). The DQT followed the principles of SAGAT, but was different in its implementation. / The DQT was applied in three studies to measure SA in the land force. The method was successively refined over the three studies. The first dealt with a Command Post exercise in which the SA of a command team was measured. It served as a pilot to investigate the strengths and weaknesses of the method. In the second study, the SA of members of an infantry section was measured in a field setting to investigate the effects of intra-section radios on SA. The environment in which the study was conducted demanded further modification of the method. The third study, also conducted in the field, involved SA measures of members of the Ground-Based Air Defence Regiment. In this case the impact of digital display on SA was investigated. / SAGAT has been demonstrated to have a high degree of sensitivity, reliability and validity in other domains. The three studies reported in the thesis produced results that were entirely consistent with those that would be expected from the SA theory and model, showing that the DQT has criterion validity. Content validity was ensured through a rigorous process. The environment in which it was implemented conferred face validity. / It will be shown that the DQT is a sound method for providing objective measures of SA in the land domain. The method produces rich data, the analysis of which may provide insights about the operator's SA in terms of each SA level (perception, comprehension and prediction), and category (friendly or enemy force and terrain). The DQT is not difficult to implement and does not require special equipment. A disadvantage is that it is effort intensive, including the requirement for a Subject Matter Expert to support the researcher during the activities. / Thesis (MEng(ComputerSystemsEng))--University of South Australia, 2006.
237

Intelligent techniques for decision support system in tactical air combat environment

Tran, Cong Minh January 2004 (has links)
The thesis presents research on decision-making in the Tactical Air Combat Environment (TACE). Decision-making occurs often in situations such as business, marketing, medicine and management. In some cases the decision can be quickly made if we have sufficient information or a clear need for the work. In complex cases involving uncertain information, the decision making process is hard and ambiguous. It is difficult to choose or to provide good solutions in areas such as medical treatment, business management or in the battlefield. The model of the tactical air combat environment decision support system is used as the trial model for the Decision Support System (DSS) for the Airborne Early Warning Command and Control (AEW&C). This system is currently designed and developed in the Air Operation Department of the Defence Science Technology Organisation (DSTO) in Australia. The cognitive work analysis (CWA) theory has been investigated and developed in recent years to analyse and develop the human system interaction process to support decision making in TACE. The situation Awareness (SA) theory is also investigated. The thesis introduces theories of decision making and the intelligent techniques that can support the decision making process. Fuzzy Logic or Expert Systems will be used to implement the heuristic knowledge. The training process derived from experience or object recognition will be good useful for the decision making process. Neural network using the back propagatino learning algorithm and its optimisation approaches will be used for this task. Usually a decision support system is made to solve problems where multi-criteria decision are involved. The database is the vital part of the decision support which contains the information or data used in the decision making process. This is where engineers and scientists use several heuristics and soft computing techinques such as learning, search and modelling of imprecise information to obtain optimal decisions. The thesis proposes hybrid intelligent techniques using a fuzzy genetic system and a fuzzy neural system to obtain decision rules automatically. The fuzzy inference system is used to process the imprecise information. Some simulation results demonstrate the difficulties in deciding the optimal quantity of membership functions; shape and parameters are also given. The last part of the thesis explicates a combination of unsupervised learning techniques for clustering the data that is proposed in order to develop decision regions for the fuzzy c mean clustering and self organisation map. It uses a feed forward neural network to classify the decision regions accurately. The clustered data is used for the inputs to the multi-layered feed forward neural network, which is trained using several higher order learning paradigms. Experimental results obtained show the proposed method is efficient. / Thesis (PhDElectronicEngineering)--University of South Australia, 2004
238

Query error detection: Using base rates to improve end user query performance

Robb, D. A. Unknown Date (has links)
No description available.
239

Leiopelma hochstetteri Fitzinger 1861 (Anura: Leiopelmatidae) habitat ecology in the Waitakere Ranges, New Zealand

Najera-Hillman, Eduardo January 2009 (has links)
Declines and extinctions of amphibian populations are a global dilemma with complex local causes, which should be viewed in the context of a much larger biodiversity crisis. As other animal groups, amphibians with restricted distributions, such as island endemics, are thought to be more vulnerable to environmental change and susceptible to population declines. In the New Zealand archipelago, the only four native species of frogs (Leiopelma hochstetteri, L. archeyi, L. hamiltoni and L. pakeka) are classified as threatened. In particular Leiopelma hochstetteri, the most widespread and abundant endemic frog species in New Zealand, now survives only in spatially fragmented populations as a result of direct or indirect human activity. Hence, it is recognised as threatened and fully protected by legislation. In the last fifty years, some L. hochstetteri populations have been studied, providing descriptive information, which may be used to assess the current status (increasing, stable or declining) of previously or never monitored populations. This thesis examines the diet and trophic level, the effects ship rats (Rattus rattus) as well as the distribution and abundance of L. hochstetteri on a habitat-use context, to provide a basis for evaluating conceivable decline-agents, and to establish a platform to design directed conservation strategies. The Waitakere Ranges are considered a Leiopelma hochstetteri conservation management unit, on which L. hochstetteri has been previously studied. This area consists of a series of hills that run roughly north–south, which are mostly covered in regenerating indigenous vegetation. Today, 60% of the Waitakere Ranges fall within a Regional Park, which together with its surrounding residential areas is afforded protection to minimise the effects of development on the region. The accessibility and conservation character of this area makes it an ideal area for the study of L. hochstetteri populations. As a first step to characterise the diet and trophic level of L. hochstetteri within streams in the Waitakere Ranges, Auckland, stable carbon and nitrogen isotope analyses were undertaken on a variety of sympatric terrestrial and aquatic plant and animal species, including adult frogs. These results showed that: 1) aquatic and terrestrial food webs were linked by terrestrial inputs into the stream; 2) invertebrate and vertebrate predators separated well into distinct trophic groups; and 3) L. hochstetteri occupied an intermediate trophic position among predators, with a diet, at least as an adult, comprising terrestrial invertebrates. Shortfin eels and banded kokopu were identified as potential predators of L. hochstetteri, but data for rats were inconclusive. The inconclusiveness of these trophic studies, with regard to the effects of ship rats on L. hochstetteri populations, lead me to evaluate the influence of a seven-year ship rat management operation on frog abundance. To achieve a reliable evaluation, the habitat characteristics that had significant influence on frog abundance were identified. Then, it was confirmed that the study areas represented similar habitats in terms of those variables, and finally the effect of the pest-management activities was evaluated. Presence/absence of pest-management operations did not have a significant effect on frog abundance. These results, together with the results of the diet and trophic level analyses, suggested that ship rats do not represent a significant threat for this frog species, at least in the Waitakere Ranges. The results of distribution and abundance investigations indicated that in the Waitakere Ranges frogs are currently widely distributed, relatively abundant and that recruitment has occurred at least in the last ten years. Additionally, in order to identify associations between habitat characteristics and frog distribution and abundance, reliable and specifically designed monitoring methodologies were developed. Although this frog is known to occur in wet areas adjacent to shaded streams in forested catchments, quantitative ecological data previously did not exist to enable characterisation of its habitat. Here, novel data were reported on the current distribution and habitat requirements of this species in the Waitakere Ranges. Statistical modelling demonstrates frogs most likely occur in small, erosive streams with coarse substrates and cold waters, surrounded by mature or undisturbed riparian vegetation, where higher abundances of frogs may be found in steep areas with stable patches of cobbles and boulders lying against larger stream bed elements within the stream channel. Anthropogenic activities, such as clearing or logging, and upstream disturbances that potentially increase silt input into streams were identified as threats to these frog species. Finally, the habitat-use information gathered during this investigation was utilised to develop a spatial decision support system (SDSS) as a tool to assess the quality and quantity of habitat available to L. hochstetteri populations associated with the Auckland Region. These results have important implications for the conservation of New Zealand native frog species and riparian stream habitat.
240

Leiopelma hochstetteri Fitzinger 1861 (Anura: Leiopelmatidae) habitat ecology in the Waitakere Ranges, New Zealand

Najera-Hillman, Eduardo January 2009 (has links)
Declines and extinctions of amphibian populations are a global dilemma with complex local causes, which should be viewed in the context of a much larger biodiversity crisis. As other animal groups, amphibians with restricted distributions, such as island endemics, are thought to be more vulnerable to environmental change and susceptible to population declines. In the New Zealand archipelago, the only four native species of frogs (Leiopelma hochstetteri, L. archeyi, L. hamiltoni and L. pakeka) are classified as threatened. In particular Leiopelma hochstetteri, the most widespread and abundant endemic frog species in New Zealand, now survives only in spatially fragmented populations as a result of direct or indirect human activity. Hence, it is recognised as threatened and fully protected by legislation. In the last fifty years, some L. hochstetteri populations have been studied, providing descriptive information, which may be used to assess the current status (increasing, stable or declining) of previously or never monitored populations. This thesis examines the diet and trophic level, the effects ship rats (Rattus rattus) as well as the distribution and abundance of L. hochstetteri on a habitat-use context, to provide a basis for evaluating conceivable decline-agents, and to establish a platform to design directed conservation strategies. The Waitakere Ranges are considered a Leiopelma hochstetteri conservation management unit, on which L. hochstetteri has been previously studied. This area consists of a series of hills that run roughly north–south, which are mostly covered in regenerating indigenous vegetation. Today, 60% of the Waitakere Ranges fall within a Regional Park, which together with its surrounding residential areas is afforded protection to minimise the effects of development on the region. The accessibility and conservation character of this area makes it an ideal area for the study of L. hochstetteri populations. As a first step to characterise the diet and trophic level of L. hochstetteri within streams in the Waitakere Ranges, Auckland, stable carbon and nitrogen isotope analyses were undertaken on a variety of sympatric terrestrial and aquatic plant and animal species, including adult frogs. These results showed that: 1) aquatic and terrestrial food webs were linked by terrestrial inputs into the stream; 2) invertebrate and vertebrate predators separated well into distinct trophic groups; and 3) L. hochstetteri occupied an intermediate trophic position among predators, with a diet, at least as an adult, comprising terrestrial invertebrates. Shortfin eels and banded kokopu were identified as potential predators of L. hochstetteri, but data for rats were inconclusive. The inconclusiveness of these trophic studies, with regard to the effects of ship rats on L. hochstetteri populations, lead me to evaluate the influence of a seven-year ship rat management operation on frog abundance. To achieve a reliable evaluation, the habitat characteristics that had significant influence on frog abundance were identified. Then, it was confirmed that the study areas represented similar habitats in terms of those variables, and finally the effect of the pest-management activities was evaluated. Presence/absence of pest-management operations did not have a significant effect on frog abundance. These results, together with the results of the diet and trophic level analyses, suggested that ship rats do not represent a significant threat for this frog species, at least in the Waitakere Ranges. The results of distribution and abundance investigations indicated that in the Waitakere Ranges frogs are currently widely distributed, relatively abundant and that recruitment has occurred at least in the last ten years. Additionally, in order to identify associations between habitat characteristics and frog distribution and abundance, reliable and specifically designed monitoring methodologies were developed. Although this frog is known to occur in wet areas adjacent to shaded streams in forested catchments, quantitative ecological data previously did not exist to enable characterisation of its habitat. Here, novel data were reported on the current distribution and habitat requirements of this species in the Waitakere Ranges. Statistical modelling demonstrates frogs most likely occur in small, erosive streams with coarse substrates and cold waters, surrounded by mature or undisturbed riparian vegetation, where higher abundances of frogs may be found in steep areas with stable patches of cobbles and boulders lying against larger stream bed elements within the stream channel. Anthropogenic activities, such as clearing or logging, and upstream disturbances that potentially increase silt input into streams were identified as threats to these frog species. Finally, the habitat-use information gathered during this investigation was utilised to develop a spatial decision support system (SDSS) as a tool to assess the quality and quantity of habitat available to L. hochstetteri populations associated with the Auckland Region. These results have important implications for the conservation of New Zealand native frog species and riparian stream habitat.

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