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Surgery and immuno modulation in Crohn’s diseaseMyrelid, Pär January 2009 (has links)
Crohn’s disease is a chronic inflammatory bowel disease with unknown origin. This study investigates the combined use of surgery and immuno modulation in Crohn’s disease. The outcome of medication and surgery in 371 operations on 237 patients between 1989 and 2006 were evaluated. Moreover the effects of prednisolone, azathioprine and infliximab on the healing of colo-colonic anastomosis in 84 mice with or without colitis were evaluated. The use of thiopurines after abdominal surgery in selected cases of severe Crohn’s disease was found to prolong the time to clinical relapse of the disease from 24 to 53 months. Patients on postoperative maintenance therapy with azathioprine had a decreased symptomatic load over time and needed fewer steroid courses. The use of thiopurines was found to be a risk factor of anastomotic complications in abdominal surgery for Crohn’s disease together with pre-operative intra-abdominal sepsis and colo-colonic anastomosis. The risk for anastomotic complications increased from 4 % in those without any of these risk factors to 13 % in those with any one and 24 % if two or three risk factors were present. In patients with two or more of these, or previously established, risk factors prior to surgery one should consider refraining from anastomosis or doing a proximal diverting stoma. Another possibility is to use a split stoma in which both ends of a future delayed anastomosis are brought out in the same ostomy hole of the abdominal wall. This method was found to significantly decrease the number of risk factors prior to the actual anastomosis as well as decreasing the risk of anastomotic complications, without increasing the number of operations or the time spent in hospital. In the animal model all three medications had an ameliorating effect on the colitis compared with placebo. Only prednisolone was found to interfere with the healing of the colo-colonic anastomoses with significantly decreased bursting pressure compared with placebo as well as azathioprine and infliximab. The association between azathioprine therapy and anastomotic complications may be due to a subgroup of patients with a more severe form of the disease who have an increased risk of such complications and also are more prone to receive intense pharmacological therapy. / Crohns sjukdom är en kronisk inflammatorisk tarmsjukdom av oklar orsak. Huvudsyftet med denna avhandling var att undersöka den kombinerade behandlingen med kirurgi och immunhämmare vid Crohns sjukdom. Utfallet av medicinsk och kirurgisk behandling vid 371 operationer på 237 patienter mellan 1989 och 2006 utvärderades. Därutöver studerades effekterna av kortison, immunhämmare och behandling med inflammationsdämpande antikroppar på läkning av tjocktarms-skarv på 84 möss med eller utan inflammation i tarmen. Vid utvalda fall med svårare form av Crohns sjukdom visade sig förebyggande behandling med immunhämmare efter kirurgi förlänga tiden till återfall av symptom från 24 till 53 månader. Patienter med immunhämmare som underhållsbehandling hade också minskade symptom under uppföljningstiden med ett minskat behov av kortison. Immunhämmande behandling inför kirurgi visade sig, liksom pågående infektion i bukhålan och sydd skarv på tjocktarmen, vara en riskfaktor för att drabbas av komplikationer vid bukkirurgi på grund av Crohns sjukdom. Risken för infektionskomplikationer i bukhålan ökade från 4 % hos dem utan någon av dessa riskfaktorer till 13 % hos dem med någon och 24 % hos dem med två eller tre riskfaktorer inför operationen. Hos patienter med två eller fler kända riskfaktorer bör man överväga att avstå från att sy en skarv på tarmen vid kirurgi eller möjligen skydda skarven med en avlastande stomi. Ett alternativ till detta är att anlägga en delad stomi där bägge ändarna av den framtida skarven tas ut genom en och samma stomiöppning i bukväggen. Denna metod med en fördröjd skarv på tarmen visade sig minska antalet kirurgiska riskfaktorer inför själva skarvningen och dessutom minska risken för tidiga infektiösa komplikationer i bukhålan, utan att vare sig öka antalet kirurgiska ingrepp eller förlänga vårdtiden på sjukhus. I en djurmodell visade sig alla tre läkemedlen ha en lindrande effekt på tarminflammation jämfört med placebo. Endast kortison visade sig påverka läkningen negativt med en sänkning av bristningstrycket i den sydda skarven på tjocktarmen, jämfört med placebo såväl som med immunhämmare och antikropps-behandling. Kopplingen mellan immunhämmare och komplikationer efter sydda skarvar på tarmen behöver alltså inte vara en direkt läkemedelseffekt. Orsaken kan istället vara att en undergrupp av Crohnpatienter har en svårare sjukdomsform som ger både ökad komplikationsrisk och större behov av intensiv medicinsk behandling.
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Unloading using auger tool and foam and experimental identification of liquid loading of low rate natural gas wellsBose, Rana 17 September 2007 (has links)
Low-pressure, low-producing natural gas wells commonly encounter liquid loading
during production. Because of the decline in the reservoir pressure and the flow
capacity, wells can fall below terminal velocity. Identifying and predicting the onset
of liquid loading allows the operators to plan and prepare for combating the liquid
loading hence saving valuable reserves and downtime. The present industrial
applications of artificial lift, wellhead pressure reduction by compressor installation
at the wellheads and reduction in tubing size are costly and often intermittent. The
thesis examines the above aspects to generate a workflow for identifying and
predicting the liquid loading conclusively and also assessing the application of
Auger Tool and foam combination towards achieving a cost effective and more
efficient solution for liquid unloading.
In chapters I-IV, I describe the process of using production surveillance software of
Halliburton Digital Consulting Services, named DSS (Dynamic Surveillance
Software), to create a workflow of identifying the liquid loaded wells based on well
data on daily basis for field personnel and engineers. This workflow also decides the most cost effective solution to handle it. Moreover, it can perform decline
analysis to predict the conditions of liquid loading.
In chapters V-VIII of the thesis, I describe the effort of handling the problem of
liquid loading in a cost effective manner by introduction of an inexpensive Auger
Tool in the bottomhole assembly and using WhiteMax surfactant soapstick from
J&J Solutions. Four different combinations of well completion and fluid were tested
for performance in respect to liquid hold up, pressure loss in the tubing, unloading
efficiency and critical flow requirement. The test facilities and instruments, along
with the operational methods, are discussed in chapter VI.
Except for the reduction of the operational envelope with the inclusion of Auger
Tool, the performance improved with the insertion of Auger Tool. The best
combination of Auger and foam system could be a result of flow modification by the
Auger Tool caused by reduced pressure loss and increase in drag coefficient and
also by reduced density and surface tension of foam.
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Decision Support System : A study of strategic decision makings in banksMao, Yanwei January 2010 (has links)
<p>The main purpose of this research is to use Hermeneutic research approach to find out how Decision Support System (DSS) is used in banks and financial services. The research started from one stance, from which the further process could be extended to reach more complete picture of Decision Support System’s usage in strategic decision makings in banks. The research is also trying to find out the drawbacks and benefits of the DSS which have been used nowadays in banks. Furthermore, the future improvements of using DSS to make better decisions related with moral and different environments are also being discussed in the research findings.</p><p>During the primary data collection, resources from different channels have been used to support the research. The primary data sources include lectures and discussion in three banks’ visiting opportunities in Stockholm, Sweden, one interview with IT Vice president from Bank of America Merrill Lynch, New York, two interviews with a professor and a director respectively from Lund University and Financial Services Innovation Centre in University College Cork, Ireland.</p><p>Experiences from both academic and practical have been shared to strength the research’s validity and trustworthiness. Hermeneutic research approach addresses through the whole research process which needs to be open-minded and flexible.</p><p>Unawareness of DSS for people who are working in banks is one of the issues today. Different embedded models regarding various functions are not so clear to bank staff; thus there is a gap between human decisions and system decisions. There is a variation of requirements between central banks, retail banks, commercial banks, investment banks. Hence there should be a differentiation when implementing a system. Banking systems are widespread systems which are influenced by environment factors, political, economic, socio-cultural and technological variables.</p>
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EcoRestore : a decision support system for the restoration of degraded rangelands in southern Africa / Anuschka Susan BaracBarac, Auschka Susan January 2003 (has links)
Land degradation is a process that causes the reduction in resource potential of natural
rangelands and occurs widespread throughout southern Africa. This process is mainly
characterized by the loss in vegetation cover, which leads to the occurrence of bare
and denuded patches, increased soil erosion, changes in species composition as well
as bush encroachment by indigenous and alien invasive plant species in savannah
areas.
Degradation of rangelands has drastically extended at an alarming rate during the last
few decades with the main causes being overstocking, extended periods of drought,
global climate change, overgrazing and general mismanagement of the land. Many
researchers, however, feel that rangeland degradation is mainly caused by a
combination of changes in land use practices and climate variability.
Land users have, however, been applying a variety of technologies over the years in
order to restore affected rangelands and mitigate the effect of degradation. These
technologies include passive and active intervention methods, aimed at restoring bare
and denuded areas and controlling indigenous bush and alien plant species
encroachment. Bush control can be carried out by applying different technologies,
involving chemical, mechanical, manual or biological control.
The focal point of this study is on bush encroachment, the factors causing the
problem, the possible ways of controlling this phenomenon and lastly the
incorporation of such information into a user-friendly Decision Support System
(DSS). The Decision Support System comprises of two databases as well as a related
expert system. Bush encroachment is a matter of great concern in most southern
African countries. This study therefore mainly included data from Namibia and to a
lesser extent, South Africa, as the main study areas, seeing that this form of
degradation greatly influences the biodiversity of rangelands in both these countries.
The Namibia Agricultural Union (NLU) identified the need for the development of a
user-friendly Decision Support System, in which case studies concerning the different
bush control technologies could be stored in a database. Restoration technologies,
regarding the occurrence of bare and denuded areas, that have been applied by the
land users over a period of time and in a specific environment in the past, have been
captured in a computerized database and expert system, serving as a Decision Support
System (DSS) and user-friendly consulting tool in a similar study, carried out by Mr.
Van der Merwe (1997). This DSS was based on CBR (Case Based Reasoning)
methodologies by which a number of case studies, that have previously been stored in
the database, can be searched by means of an expert system approach to advise the
land user concerning the most appropriate solution (action) to similar degradation
problems. The DSS developed by Mr. Van der Merwe was never published or made
accessible to the land user in a format that could be consulted by either CD-ROM or
the internet. Seeing that the NLU identified the need for a similar DSS containing
bush control technologies, it was decided to incorporate both these databases into a
single DSS, concerning bush control as well as the restoration of bare and denuded
patches. The newly converted DSS is currently known as EcoRestore and consists on
two databases: Grass Expert, which focuses on technologies to reclaim degraded
rangelands, and Bush Expert, which is more focused on the control of bush
encroachment and combating of alien invasives.
As mentioned, this study focussed on the development of the Bush Expert database
and will therefore only include results, discussions and conclusions of these case
studies.
The case studies in the Bush Expert database consist of results obtained by means of a
questionnaire completed by the land user, in collaboration with the agricultural
extension officer, as well as a quantitative vegetation assessment, to determine the
success rate of the applied technology.
The Bush Expert questionnaire, comprises of questions concerning personal
information of the land user (e.g. location of the farm), the situation on the farm
before bush control was applied (e.g. information on the environmental factors, such
as density of problem trees), as well as the type of control technology applied and the
situation of the rangeland after control (e.g. establishment of the herbaceous species).
The quantitative vegetation assessments involved the sampling of the woody and
herbaceous components in the area where a specific control technology was applied.
The density and height classes of the woody component were determined by means of
the belt-transect method. By using the descending-point method, the herbaceous
component was surveyed to determine the abundance/frequency of the annual and
perennial grass species.
In order to increase the success of any restoration project, it is important to take the
existing indigenous knowledge of local land users, concerning the problem of
degradation and mitigation thereof, into consideration. By doing so, the local people
and communities have greater control and responsibility over their resources and are
able to command a greater range and level of resourcefulness. Taking indigenous
knowledge into consideration finally enables the local land users to actively
participate in and influence higher-level decision-making processes by which they are
affected.
A total of 175 case studies in Namibia and nine case studies in South Africa were
surveyed. The Namibian case studies were surveyed in the central and northern arid
and semi-arid regions, and South African case studies in a limited location within the
Limpopo Province. Only 100 of the Namibian case studies have thus far been
incorporated into the Bush Expert database.
Multivariate data analyses techniques, analysis of variance and correlation analyses
were used to analyse the data obtained from the questionnaires and quantitative
vegetation surveys. Results were represented in the form of histogrammes, tables and
multivariate analysis ordinations.
From the results obtained for the Bush Expert database, it was clear that chemical
control technologies were most often applied in Namibian and South African case
studies (61%). The herbicides most commonly applied as chemical control technology
in Namibia included Grazer (20%) and Savana (15%), whilst in South Africa these
included Access (33.3%) and Tordon Super (33.3%). Herbicides were mostly applied
by means of aerial application (46%) methods in Namibia and as cut-stump treatment
(55.5%) by means of knapsack spraying or with a brush in South Africa.
The dominant woody species causing bush encroachment problems in Namibia were
found to be Acacia mellifera, Acacia reficiens and Dichrostachys cinerea, whereas in
South Africa these species included Dichrostachys cinerea, Acacia erubescens and
Acacia karroo.
The wood of the controlled problem species (dead woody material) is mostly not
utilized after control, but rather left on the land to disintegrate and thus contribute to
the organic material content in the soil. Dead branches are also used for brush packing,
which forms and ideal micro-climate for the germination and establishment of grass
seeds, which serves as an erosion control medium and protects grass seedlings against
grazing impacts. Some land users do however produce charcoal from certain
controlled woody species, in order to recover some of the input costs of bush control.
The majority of the case study sites (68%) in Namibia occurred within the 300-450
mm short- and long-term rainfall zones and in South Africa the majority of case study
sites occurred within the short-term rainfall zone of 550-600 mm (66.6%) and 400-
500 mm long-term rainfall zone (55.5%).
Case studies where chemical and manual bush control technologies were applied
indicated the highest success rates after control (81.7% and 75.2% respectively).
Success rate as an entity was greatly influenced by the type of control technology
applied, the density of the problem woody species after bush control as well as
environmental variables such as rainfall and soil clay percentage.
No definite trend could be determined concerning the application of a specific bush
control technology and a certain problem species. Land users tend to apply a chosen
control technology, according to the resources available, such as labour, mechanical
implements and finances. The only positive correlation between control technologies
and the type of problem species could be found regarding Dichrostachys cinerea. This
species was mainly chemically controlled by means of the application of certain
herbicides.
The most important lesson to be learnt from the surveys completed in the two
countries is that it is an absolute necessity to apply a proper after-care programme as a
management practice following the initial control of problem woody species. The
implementation of after-care determines the final success rate of any applied bush
control technology as a restoration practice within a rangeland. Only 11% of the case
studies surveyed for Namibia and South Africa indicated the implementation of an
after-care programme, which usually involved biological control (e.g. browsing by
boer goats or the use of controlled or accidental natural veld fires).
The EcoRestore Decision Support System is currently available as an online webversion
(www.puk.ac.za/EcoRestore), as well as a CD-ROM version. The CD-ROM
version is available in a package containing the CD and user's manual. An example of
the package is included in this dissertation.
In consulting the databases through question-and-answer procedures, the best action
will be proposed to the land user for future rangeland restoration, either the
reclamation of denuded areas or the control of bush encroachment. Since the case
studies are based on past and existing experiences and research, the land user will
have an indication of the expected outcome, should the same advised technology be
applied.
The EcoRestore DSS does not only offer a consulting tool for extension workers and
technicians, but also creates networking and participation between land users and
researchers, both locally and between neighbouring countries. The DSS is linked to
other national and international websites and databases, to offer users a wider range of
information and technologies with regard to agricultural and conservation practices.
Better awareness is created amongst land users concerning the problem of rangeland
degradation, which might encourage closer monitoring of the degradation and
mitigation processes.
The EcoRestore DSS was developed in such a way for it to be as user-friendly as
possible, in order to reach as many parties involved in current or future restoration
programmes. This study involved the development of the first version of the DSS
(Version 1.0) and is thus only the prototype system. It is proposed that the Bush
Expert database of the EcoRestore DSS, will be expanded in future and additional
bush control case studies from other southern African countries will be included. The
addition of such case studies will ultimately increase the effectivity of this DSS. / Thesis (M.Sc. (Botany))--North-West University, Potchefstroom Campus, 2004.
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EcoRestore : a decision support system for the restoration of degraded rangelands in southern Africa / Anuschka Susan BaracBarac, Auschka Susan January 2003 (has links)
Land degradation is a process that causes the reduction in resource potential of natural
rangelands and occurs widespread throughout southern Africa. This process is mainly
characterized by the loss in vegetation cover, which leads to the occurrence of bare
and denuded patches, increased soil erosion, changes in species composition as well
as bush encroachment by indigenous and alien invasive plant species in savannah
areas.
Degradation of rangelands has drastically extended at an alarming rate during the last
few decades with the main causes being overstocking, extended periods of drought,
global climate change, overgrazing and general mismanagement of the land. Many
researchers, however, feel that rangeland degradation is mainly caused by a
combination of changes in land use practices and climate variability.
Land users have, however, been applying a variety of technologies over the years in
order to restore affected rangelands and mitigate the effect of degradation. These
technologies include passive and active intervention methods, aimed at restoring bare
and denuded areas and controlling indigenous bush and alien plant species
encroachment. Bush control can be carried out by applying different technologies,
involving chemical, mechanical, manual or biological control.
The focal point of this study is on bush encroachment, the factors causing the
problem, the possible ways of controlling this phenomenon and lastly the
incorporation of such information into a user-friendly Decision Support System
(DSS). The Decision Support System comprises of two databases as well as a related
expert system. Bush encroachment is a matter of great concern in most southern
African countries. This study therefore mainly included data from Namibia and to a
lesser extent, South Africa, as the main study areas, seeing that this form of
degradation greatly influences the biodiversity of rangelands in both these countries.
The Namibia Agricultural Union (NLU) identified the need for the development of a
user-friendly Decision Support System, in which case studies concerning the different
bush control technologies could be stored in a database. Restoration technologies,
regarding the occurrence of bare and denuded areas, that have been applied by the
land users over a period of time and in a specific environment in the past, have been
captured in a computerized database and expert system, serving as a Decision Support
System (DSS) and user-friendly consulting tool in a similar study, carried out by Mr.
Van der Merwe (1997). This DSS was based on CBR (Case Based Reasoning)
methodologies by which a number of case studies, that have previously been stored in
the database, can be searched by means of an expert system approach to advise the
land user concerning the most appropriate solution (action) to similar degradation
problems. The DSS developed by Mr. Van der Merwe was never published or made
accessible to the land user in a format that could be consulted by either CD-ROM or
the internet. Seeing that the NLU identified the need for a similar DSS containing
bush control technologies, it was decided to incorporate both these databases into a
single DSS, concerning bush control as well as the restoration of bare and denuded
patches. The newly converted DSS is currently known as EcoRestore and consists on
two databases: Grass Expert, which focuses on technologies to reclaim degraded
rangelands, and Bush Expert, which is more focused on the control of bush
encroachment and combating of alien invasives.
As mentioned, this study focussed on the development of the Bush Expert database
and will therefore only include results, discussions and conclusions of these case
studies.
The case studies in the Bush Expert database consist of results obtained by means of a
questionnaire completed by the land user, in collaboration with the agricultural
extension officer, as well as a quantitative vegetation assessment, to determine the
success rate of the applied technology.
The Bush Expert questionnaire, comprises of questions concerning personal
information of the land user (e.g. location of the farm), the situation on the farm
before bush control was applied (e.g. information on the environmental factors, such
as density of problem trees), as well as the type of control technology applied and the
situation of the rangeland after control (e.g. establishment of the herbaceous species).
The quantitative vegetation assessments involved the sampling of the woody and
herbaceous components in the area where a specific control technology was applied.
The density and height classes of the woody component were determined by means of
the belt-transect method. By using the descending-point method, the herbaceous
component was surveyed to determine the abundance/frequency of the annual and
perennial grass species.
In order to increase the success of any restoration project, it is important to take the
existing indigenous knowledge of local land users, concerning the problem of
degradation and mitigation thereof, into consideration. By doing so, the local people
and communities have greater control and responsibility over their resources and are
able to command a greater range and level of resourcefulness. Taking indigenous
knowledge into consideration finally enables the local land users to actively
participate in and influence higher-level decision-making processes by which they are
affected.
A total of 175 case studies in Namibia and nine case studies in South Africa were
surveyed. The Namibian case studies were surveyed in the central and northern arid
and semi-arid regions, and South African case studies in a limited location within the
Limpopo Province. Only 100 of the Namibian case studies have thus far been
incorporated into the Bush Expert database.
Multivariate data analyses techniques, analysis of variance and correlation analyses
were used to analyse the data obtained from the questionnaires and quantitative
vegetation surveys. Results were represented in the form of histogrammes, tables and
multivariate analysis ordinations.
From the results obtained for the Bush Expert database, it was clear that chemical
control technologies were most often applied in Namibian and South African case
studies (61%). The herbicides most commonly applied as chemical control technology
in Namibia included Grazer (20%) and Savana (15%), whilst in South Africa these
included Access (33.3%) and Tordon Super (33.3%). Herbicides were mostly applied
by means of aerial application (46%) methods in Namibia and as cut-stump treatment
(55.5%) by means of knapsack spraying or with a brush in South Africa.
The dominant woody species causing bush encroachment problems in Namibia were
found to be Acacia mellifera, Acacia reficiens and Dichrostachys cinerea, whereas in
South Africa these species included Dichrostachys cinerea, Acacia erubescens and
Acacia karroo.
The wood of the controlled problem species (dead woody material) is mostly not
utilized after control, but rather left on the land to disintegrate and thus contribute to
the organic material content in the soil. Dead branches are also used for brush packing,
which forms and ideal micro-climate for the germination and establishment of grass
seeds, which serves as an erosion control medium and protects grass seedlings against
grazing impacts. Some land users do however produce charcoal from certain
controlled woody species, in order to recover some of the input costs of bush control.
The majority of the case study sites (68%) in Namibia occurred within the 300-450
mm short- and long-term rainfall zones and in South Africa the majority of case study
sites occurred within the short-term rainfall zone of 550-600 mm (66.6%) and 400-
500 mm long-term rainfall zone (55.5%).
Case studies where chemical and manual bush control technologies were applied
indicated the highest success rates after control (81.7% and 75.2% respectively).
Success rate as an entity was greatly influenced by the type of control technology
applied, the density of the problem woody species after bush control as well as
environmental variables such as rainfall and soil clay percentage.
No definite trend could be determined concerning the application of a specific bush
control technology and a certain problem species. Land users tend to apply a chosen
control technology, according to the resources available, such as labour, mechanical
implements and finances. The only positive correlation between control technologies
and the type of problem species could be found regarding Dichrostachys cinerea. This
species was mainly chemically controlled by means of the application of certain
herbicides.
The most important lesson to be learnt from the surveys completed in the two
countries is that it is an absolute necessity to apply a proper after-care programme as a
management practice following the initial control of problem woody species. The
implementation of after-care determines the final success rate of any applied bush
control technology as a restoration practice within a rangeland. Only 11% of the case
studies surveyed for Namibia and South Africa indicated the implementation of an
after-care programme, which usually involved biological control (e.g. browsing by
boer goats or the use of controlled or accidental natural veld fires).
The EcoRestore Decision Support System is currently available as an online webversion
(www.puk.ac.za/EcoRestore), as well as a CD-ROM version. The CD-ROM
version is available in a package containing the CD and user's manual. An example of
the package is included in this dissertation.
In consulting the databases through question-and-answer procedures, the best action
will be proposed to the land user for future rangeland restoration, either the
reclamation of denuded areas or the control of bush encroachment. Since the case
studies are based on past and existing experiences and research, the land user will
have an indication of the expected outcome, should the same advised technology be
applied.
The EcoRestore DSS does not only offer a consulting tool for extension workers and
technicians, but also creates networking and participation between land users and
researchers, both locally and between neighbouring countries. The DSS is linked to
other national and international websites and databases, to offer users a wider range of
information and technologies with regard to agricultural and conservation practices.
Better awareness is created amongst land users concerning the problem of rangeland
degradation, which might encourage closer monitoring of the degradation and
mitigation processes.
The EcoRestore DSS was developed in such a way for it to be as user-friendly as
possible, in order to reach as many parties involved in current or future restoration
programmes. This study involved the development of the first version of the DSS
(Version 1.0) and is thus only the prototype system. It is proposed that the Bush
Expert database of the EcoRestore DSS, will be expanded in future and additional
bush control case studies from other southern African countries will be included. The
addition of such case studies will ultimately increase the effectivity of this DSS. / Thesis (M.Sc. (Botany))--North-West University, Potchefstroom Campus, 2004.
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Comparação dos modelos hidrológicos presentes no SSD ABC6 aplicados a uma bacia urbana / Comparison of hydrological models present in the DSS ABC6 applied to an urban watershedMarcus Vinícius Galbetti 08 July 2015 (has links)
No Brasil, o processo de urbanização caracterizou-se pela falta de planejamento e infraestrutura adequada, potencializando os impactos advindos das enchentes e inundações. Para mitigá-los, é necessária a realização de estudos hidrológicos que busquem compreender e representar o comportamento da bacia hidrográfica frente aos eventos chuvosos. Uma das ferramentas mais utilizadas para a execução dessa tarefa são os Sistemas de Suporte à Decisão (SSDs) aplicados na área de recursos hídricos, destacando-se o Sistema de Suporte a Decisões para Análise de Ondas de Cheias em Bacias Complexas (ABC6). O ABC6 caracteriza-se por ser um software brasileiro, gratuito e apresentar diversos modelos de determinação da precipitação efetiva e de geração de hidrogramas sintéticos. Quando os dados hidrológicos da área de estudo, como precipitação e vazão, encontram-se disponíveis, os parâmetros desses modelos podem ser determinados. Caso contrário, faz-se necessário estima-los por meio de formulações empíricas, sendo questionável a aplicação dessas formulações em áreas com características diferentes às de sua determinação. Dessa forma, a proposta do presente trabalho consistiu em avaliar o desempenho dos modelos presentes no ABC6, utilizando suas formulações empíricas para estimar o tempo de concentração e os parâmetros dos modelos de precipitação efetiva e de geração de hidrogramas sintéticos de uma bacia hidrográfica em processo de urbanização. Os resultados obtidos colocaram em xeque a validade dos valores dos parâmetros sugeridos em literatura técnica, do modelo do SCS para a determinação da precipitação efetiva e das rotinas de cálculo do ABC6 para os modelos de Horton e de Green-Ampt. Os resultados demonstraram a necessidade da atualização das rotinas de cálculo presentes no ABC6, de forma a torna-lo mais robusto, e da elaboração de um manual técnico detalhado de suas rotinas computacionais, orientando ao usuário de forma a extrair o máximo de sua potencialidade em estudos hidrológicos. Demonstrou-se, também, a necessidade de estudos regionalizados, de forma a incorporar as características e peculiaridades de cada região aos parâmetros a serem utilizados. / In Brazil, the urbanization process was characterized by the lack of planning and adequate infrastructure, strengthening the arising of floods and flooding. In order to mitigate them, it is necessary to conduct hydrological studies that seek to understand and represent the behavior of the watershed when facing rainfall events. One of the most used tools to perform this task is the Decision Support Systems (DSS) applied in the water resources area, highlighting the Decision Support System for Flood Wave Analysis in Complex Watersheds (ABC6). The ABC6 is characterized by being a free Brazilian software and it presents many models to determine the effective precipitation and to generate synthetic hydrographs. When the hydrological data of the study area are available, such as precipitation and flow, the models parameters can be determined. Otherwise, it is necessary to estimate them through empirical formulations so that the application of these formulations is questionable in areas with different characteristics from those of their determination. Thus, the purpose of this study was to assess the performance of the models presented in ABC6 by using their empirical formulations in order to estimate the time of concentration and the model parameters of effective precipitation and synthetic hydrograph generation for a watershed in the process of urbanization. The results put into question the validity of the parameters values suggested in the technical literature of the SCS model, which is used for the effective precipitation determination and the ABC6 calculation routines for models of Horton and Green-Ampt. The results presented the need of updating the calculation routines presented in the ABC6 in order to make it more robust, and the need of the elaboration of a detailed technical manual of its computational routines, guiding the user in order to make the most of its potential in hydrological studies. In addition, it has been demonstrated a need for regionalized studies in order to incorporate the features and characteristics of each region to the parameters to be used.
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Application of voice recognition input to decision support systemsDrake, Robert Gervase 12 1900 (has links)
Approved for public release; distribution is unlimited / The goal of this study is to provide a single source of data that enables the selection of an appropriate voice recognition (VR) application for a decision support system (DSS) as well as for other computer applications. A brief background of both voice recognition systems and decision supports systems is provided with special emphasis given to the dialog component of DSS. The categories of voice recognition discussed are human factors, environmental factors, situational factors, quantitative factors, training factors, host computer factors, and experiments and research. Each of these areas of voice recognition is individually analyzed, and specific references to applicable literature are included. This study also includes appendices that contain: a glossary (including definitions) of phrases specific to both decision support system and voice recognition systems, keywords applicable to this study, an annotated bibliography (alphabetically and by specific topics) of current VR systems literature containing over 200 references, an index of publishers, a complete listing of current commercially available VR systems. / http://archive.org/details/applicationofvoi00drak / Lieutenant, United States Navy
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Functional analysis of the role of interferon gamma through the characterisation of conditional interferon gamma receptor two mouse mutantsForman, Ruth January 2011 (has links)
The data presented within this thesis shows the generation and characterisation of a complete-, macrophage/granulocyte- and T cell-specific IFNγR2 deficient mouse mutant. This mutant mouse is a valuable tool in dissecting the mechanism of action of the pleiotrophic cytokine IFNγ.The global mutant mouse was tested in three models in vivo - DSS induced colitis, Trichuris muris infection and EAE. The aim of the DSS-induced colitis model was to test the role of IFNγ in the innate immune system and, despite previous reports demonstrating IFNγ deficient mice are protected from DSS-colitis, our IFNγR2 deficient mice displayed equal or more severe colitis than control mice. We hypothesise that this discrepancy is due to differences in the gut microbiota.The Trichuris muris model was utilised as a method of examining the role of IFNγ in the adaptive immune system. The complete IFNγR2 mutant was resistant to a low dose T. muris infection; however, neither the T cell specific nor the macrophage/granulocyte specific mutant duplicated the resistant phenotype observed in the global knock-out mice. Analysis of a double conditional T cell and macrophage/granulocyte specific IFNγR2 mutant produced inconsistent results. Initial experiments suggested that, in combination, these deficiencies are sufficient to duplicate the resistant phenotype observed in the global mutant mice, but this was not reproducible.The final in vivo model that we used to analyse IFNγR2 mutant mice was EAE. This model was chosen as, for a long time, the mechanism of action and the involvement of IFNγ in EAE has been a matter of uncertainty. These results demonstrated that global IFNγR2 mutant mice demonstrate an atypical phenotype, with no signs of recovery. In contrast, control mice develop classical EAE symptoms with almost complete recovery prior to the termination of the experiment. The IFNγ receptor mutant mouse generated will be of great value to the scientific community as IFNγ has been demonstrated to play a role in multiple diseases and this tool allows the mechanism of action of this cytokine to be unravelled.
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Using Diagnostic Decision Support Systems to Reduce Diagnostic Error: A Survey of Critical Care PhysiciansJones, Elizabeth Susann 05 1900 (has links)
The purpose of this study is to investigate the use of decisions support systems (DSS) by critical care physicians and to address the following questions: Does the use of a decision support system during diagnosis reduce diagnostic error and how are decision support systems used by critical care physicians? There are no studies that address these research questions in a clinical setting. The information assessment method (IAM) was used to guide the development of the survey questions. Critical care physicians from the University of Oklahoma Health Sciences Center were surveyed. Chi squared test for independence was used to determine the relationship between DSS use and diagnostic error rates. There were three main findings of the study: (1) use of a DSS by a critical care physician can decrease diagnostic error by up to 60%; (2) 56% of critical care physicians are using a DSS during diagnosis to learn something new, confirm something they already knew, and/or to reassure themselves; and (3) the increased use of a DSS by critical care physicians can lead to a decrease in the belief of the ability of a DSS to reduce diagnostic error.
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Data-Driven Decision Support Systems for Product Development - A Data Exploration Study Using Machine LearningAeddula, Omsri January 2021 (has links)
Modern product development is a complex chain of events and decisions. The ongoing digital transformation of society, increasing demands in innovative solutions puts pressure on organizations to maintain, or increase competitiveness. As a consequence, a major challenge in the product development is the search for information, analysis, and the build of knowledge. This is even more challenging when the design element comprises complex structural hierarchy and limited data generation capabilities. This challenge is even more pronounced in the conceptual stage of product development where information is scarce, vague, and potentially conflicting. The ability to conduct exploration of high-level useful information using a machine learning approach in the conceptual design stage would hence enhance be of importance to support the design decision-makers, where the decisions made at this stage impact the success of overall product development process. The thesis aims to investigate the conceptual stage of product development, proposing methods and tools in order to support the decision-making process by the building of data-driven decision support systems. The study highlights how the data can be utilized and visualized to extract useful information in design exploration studies at the conceptual stage of product development. The ability to build data-driven decision support systems in the early phases facilitates more informed decisions. The thesis presents initial descriptive study findings from the empirical studies, showing the capabilities of the machine learning approaches in extracting useful information, and building data-driven decision support systems. The thesis initially describes how the linear regression model and artificial neural networks extract useful information in design exploration, providing support for the decision-makers to understand the consequences of the design choices through cause-and-effect relationships on a detailed level. Furthermore, the presented approach also provides input to a novel visualization construct intended to enhance comprehensibility within cross-functional design teams. The thesis further studies how the data can be augmented and analyzed to extract the necessary information from an existing design element to support the decision-making process in an oral healthcare context.
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