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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.
11

Oh G-d, A Borderline: Clinical Diagnostics As Fundamental Attribution Error

Schmalz, Jonathan 12 1900 (has links)
Researchers raise concerns that the diagnostic approach can create stigma and lead to clinical inferences that focus on dispositional characteristics at the expense of situational variables. From social cognitive theory to strict behavioral approaches there is broad agreement that situation is at least as important as disposition. The present study examined the clinical inferences of graduate student clinicians randomly presented a diagnosis (borderline PD) or no diagnosis and either randomly given context information or no context information before watching a videotaped clinical interaction of a fabricated client. Responses to a questionnaire assessing dispositional or situational attributions about the client’s behavior indicated a diagnosis of borderline personality disorder did not significantly increase dispositional attributions and did not significantly moderate the importance of contextual factors. A notable difference between the attributions made by psychodynamic and third wave behavioral respondents was observed. Conceptual and experimental limitations as well as future directions are discussed.
12

Extraction of DTM from Satellite Images Using Neural Networks

Tapper, Gustav January 2016 (has links)
This thesis presents a way to generate a Digital Terrain Model (dtm) from a Digital Surface Model (dsm) and multi spectral images (including the Near Infrared (nir) color band). An Artificial Neural Network (ann) is used to pre-classify the dsm and multi spectral images. This in turn is used to filter the dsm to a dtm. The use of an ann as a classifier provided good results. Additionally, the addition of the nir color band resulted in an improvement of the accuracy of the classifier. Using the classifier, a dtm was easily extracted without removing natural edges or height variations in the forests and cities. These challenges are handled with great satisfaction as compared to earlier methods.
13

Nyanser av beroende : En kvantitativ studie om substansbruk och beroende i den svenska vuxna befolkningen

Berggren, Emelie, Björksten, Johanna January 2016 (has links)
The ambition of the study Nyanser av beroende is to analyze and problematize the concept of addiction. A broader aim is to investigate if it in the Swedish population exists different patterns of addiction and how these patterns then look like. The empirical material constitutes of Negativa konsekvenser av ANDT-bruk i den svenska vuxna befolkningen 2014. The selection consists of 26 257 individuals with a response rate of 59, 3 percent (N=15 576). The individuals that at some time during the last year used any narcotic substance and fulfilled at least one of the addiction criterias in the diagnose manual DSM-IV are subjects to the analysis (N=560). By the analyze method of Latent klassanalys (LCA), patterns of addiction have been investigated. The theoretical framework consists of medical and social addiction theory. This to see how different patterns of addiction comply with the medical and social perspectives that can be found in DSM-IV. In the latent class analysis, four different groups with different patterns of addiction are identified: Kontrollförlust, Försökt minska intag, Hard core gruppen och Tolerans. The group’s patterns have further on been connected with sociodemographic factors and substance use. The result of this study indicate that addiction is not a homogeneous concept but that there are differences concerning patterns of use and sociodemographic factors.
14

The structure of common and severe psychopathology: analyses of syndromes and symptoms

Chmielewski, Michael Scott 01 May 2012 (has links)
One of the main goals of research in clinical psychology is to enhance the understanding and conceptualization of psychopathology. As such, it is essential that the model used to classify mental illness be as valid as possible. The Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev; DSM-IV-TR, American Psychiatric Association, 2000) provides the current model of psychopathology. However, there has been growing dissatisfaction with the current version of the DSM and there is an increasing view that the DSM taxonomy is scientifically unsound (Brown & Barlow, 2005; Watson & Clark, 2006; Widiger & Samuel, 2005). Quantitative structural models of psychopathology (e.g., Internalizing/Externalizing; Krueger, 1999) have provided an alternative to the DSM model and have greatly advanced the conceptualization of psychopathology. Although these models represent a significant improvement they still have several limitations. First, they exclude many of the "severe" disorders (e.g., psychotic disorders). Second, the placement of some disorders (e.g., OCD and PTSD) in the model has not been consistent. Finally, they are based on categorical diagnoses, which are less valid and reliable than dimensional alternatives (Markon, Chmielewski, & Miller, 2011). Thus, the use of categorical diagnosis as the foundation for empirical models of psychopathology likely results in suboptimal models. Moreover, it has been argued that many diagnoses are excessively heterogeneous, suggesting that analyzing the symptoms that underlie the disorders could result in more fine-grained models that more closely "carves nature at its joints." The current study addresses the limitations of current quantitative models to create an expanded model of psychopathology that likely has increased validity. Structural analyses were conducted at both the syndromal level (to serve as a proxy for dimensional versions of DSM diagnosis) and the symptom level in a large patient sample using both self-report and interview data. A three-factor model, containing Internalizing, Externalizing, and Psychoticism/Oddity dimensions emerged across both sets of analyses The emergence of this model at both the syndromal and symptom level provides strong evidence that a third higher order Psychoticism/Oddity dimension is necessary for a more complete model of psychopathology. The association of these dimensions with normal personality traits and other external correlates also was examined and implications for the conceptualization of psychopathology are discussed.
15

Using epidemiology to inform classification in psychiatry

Slade, Tim, Psychiatry, Faculty of Medicine, UNSW January 2002 (has links)
Classification systems in psychiatry are a work in progress. Therefore, continued efforts to improve their validity are necessary. Epidemiology provides a scientific method to assess the extent of psychiatric morbidity in community populations. However, data from epidemiological surveys have also contributed, either directly or indirectly, to many changes in the classification systems. Recent reviews of the current state of psychiatric classification indicate four unresolved issues: 1) the presence of two differing classification systems, 2) the role of the clinical significance criterion in differentiating psychopathology from normality, 3) the relationship of the exclusion criteria to the co-occurrence of psychiatric disorder pairs, and 4) the relative validity of categorical versus dimensional conceptualizations of psychiatric disorders. The current thesis examines these four unresolved issues, using data from a large-scale epidemiological survey of psychiatric disorders. With regard to GAD, differences in diagnostic criteria between DSM-IV and ICD-10 resulted in different types of cases identified, despite similarities in prevalence. The DSM-IV diagnostic criterion for clinical significance impacted, albeit to different degrees, on the prevalence, health service use and impairment of five disorders. The exclusion criteria in both DSM-IV and ICD-10 were significantly related to the patterns of co-occurrence found in the data. Using the example of depression, symptoms were more consistent with a dimensional rather than a categorical structure. A specific research agenda is proposed, the aim of which is to provide possible avenues of research that may benefit revisions to classification systems and the conduct of epidemiological surveys. This research agenda contains a number of suggestions. Future revisions will benefit from an explicit understanding of the differences between the classification systems. Better definitions of the concepts of clinical significance and psychiatric disorder are required. The co-occurrence of disorder pairs in epidemiological data informs understanding of the exclusion criteria, but the validity of these criteria relies on different data. Dimensional models of classification may yield more information than categorical models, and methods for incorporating them in large-scale surveys are proposed. It is concluded that epidemiological data should continue to play a significant part in the refinement of psychiatric classification.
16

Demand side management on an intricate multi-shaft pumping system from a single point of control / Shane Thein

Thein, Shane January 2007 (has links)
Thesis (M.Ing. (Electrical Engineering))--North-West University, Potchefstroom Campus, 2007.
17

Demand side management on an intricate multi-shaft pumping system from a single point of control / Shane Thein

Thein, Shane January 2007 (has links)
Eskom, the sole supplier of electricity in South Africa is facing an energy crisis. This is due to the steady increase in demand for electricity in South Africa. Low electricity prices in South Africa have helped the energy intensive industries of South Africa to be more competitive. Unfortunately this has resulted in poor energy efficiency practices and has hampered incentives to save energy. To address this problem, Eskom initiated a Demand Side Management (DSM) programme. DSM is beneficial to both Eskom and the client. However, due to the high cost of implementing such projects, it is feasible to implement it only on sites where the load shift potential is high enough for Eskom to benefit. The mining industry has been targeted for DSM programmes. This is due to the existence of a large mining sector in South Africa and to its energy intensive nature. Most mining operations require large amounts of water which is used to cool the underground environment and so ensure productivity and the safety of the workers. Due to the large amounts of water needed for mining, the electricity usage of these pumping systems is very high. If the use of this electricity can be optimised by implementing DSM principles, this will result in the long term savings of costs for the mines involved. The majority of pumping systems found on mines are single shaft systems. Individually these systems have a very high DSM potential. However, if multiple shaft systems can be used for DSM, the benefits will be far greater. Furthermore, combining several sites with an interconnected water pumping system will increase the potential for DSM and enable sites where individually the potential is too low to be feasible for a DSM project to raise their potential. This will result in more sites where DSM projects can be implemented and more clients who can benefit from the DSM programme. The purpose of this study is to investigate and implement a DSM project on an intricate multi-shaft mine pumping system which will be controlled from a single point. The project required a detailed investigation of the pumping systems on each shaft and how the water system is interlinked between the shafts. This project was carried out on Beatrix Mine Shafts 1, 2 and 3. The pumping systems were analysed and simulated according to the specific constraints and requirements that were specified by the mine. During the investigation and implementation of this project, possible efficiency improvements on certain pump stations were discovered and implemented. The improvements enabled both an increase in water flow to the surface and a decrease in power consumption. Due to this load reduction, the savings achieved were higher than those found in most load shifting projects. Moreover, additional infrastructures were installed to ensure communication between pumping systems. Once the simulation and optimisation of the control system was completed, the pumping system network was automated. The load shift resulted in a ± 3.5 MW shift in the morning peak demand period and a ± 6.0 MW shift in the evening peak demand period. This load shift has resulted in an average cost saving of R 80 000 per month during summer tariff period, and R 300 000 per month during winter tariff period. This saving result was calculated by taking load reduction into account. This project has shown that a DSM project can be implemented successfully, given the necessary historical data and expertise, on a pumping system that is interconnected between multiple shafts. / Thesis (M.Ing. (Electrical Engineering))--North-West University, Potchefstroom Campus, 2007.
18

Electricity cost optimisation of a surface potable water pump system / M.P. Slade

Slade, Michael Peter January 2007 (has links)
South Africa is fast approaching an era where its electrical energy demand will surpass the generating capacity of it's primary utility. The reason for this is due to the fact that over the past 10 years, the economic growth in South Africa has increased considerably and has become very energy intensive. South African electrical energy consumption is currently estimated to be growing at a rate of around 1 000 MW per year. Due to the electrical energy demand being the greatest during peak-times, Eskom has introduced various "time of use" tariff structures, such as Megaflex and Ruraflex. These two tariff structures differentiate between standard, peak and off-peak periods of the day, as well as different seasons of the year. The tariffs for these different scenarios are adjusted such that the consumers are persuaded into avoiding unnecessary electrical energy consumption during peak periods. It has been identified that electrical energy consumption can be split into two categories. One of the categories considers sectors where there are a large number of electrical energy consumers, each utilising a negligible amount of power. The other category considers sectors where there are few electrical energy consumers, each utilising large amounts of power. This therefore means that the consumers in the latter category have a great potential in implementing more efficient ways of consuming power. In order to try and control the electrical energy demand problem in South Africa, Eskom has implemented a DSM (Demand Side Management) programme in order to help the larger energy consumers in shifting their peak-time loads to off-peak periods. If the client wishes to shift their load to off-peak periods, Eskom will assist by funding all costs to carry out such a project. According to Eskom's monitoring and verification team, Eskom's DSM initiative has proven to be highly successful. Since the inception of Eskom's DSM programme in 2003, up until the end of 2005, an accumulated total load reduction of 296.3 MW has successfully been realised. At present, most water distribution schemes have been developed without making use of Eskom's DSM initiative. As these schemes consume considerable amounts of electrical energy, they are prime candidates for an initiative such as Eskom's DSM initiative. It had previously been identified that the Vaal Gamagara Water Scheme, situated in Delportshoop, was a prime candidate for Eskom's DSM initiative. Presented in this dissertation are the findings of the DSM investigation. Although the project has yet to be implemented, the proposed intervention methodology was manually tested, where a 3 MW load shift in the evening peak and a 3.6 MW load shift in the morning peak was achieved. If the current intervention methodology is maintained, the annual savings will be in the region of R 830,000.00. / Thesis (M.Ing. (Electrical Engineering))--North-West University, Potchefstroom Campus, 2008.
19

Demand side management on an intricate multi-shaft pumping system from a single point of control / Shane Thein

Thein, Shane January 2007 (has links)
Eskom, the sole supplier of electricity in South Africa is facing an energy crisis. This is due to the steady increase in demand for electricity in South Africa. Low electricity prices in South Africa have helped the energy intensive industries of South Africa to be more competitive. Unfortunately this has resulted in poor energy efficiency practices and has hampered incentives to save energy. To address this problem, Eskom initiated a Demand Side Management (DSM) programme. DSM is beneficial to both Eskom and the client. However, due to the high cost of implementing such projects, it is feasible to implement it only on sites where the load shift potential is high enough for Eskom to benefit. The mining industry has been targeted for DSM programmes. This is due to the existence of a large mining sector in South Africa and to its energy intensive nature. Most mining operations require large amounts of water which is used to cool the underground environment and so ensure productivity and the safety of the workers. Due to the large amounts of water needed for mining, the electricity usage of these pumping systems is very high. If the use of this electricity can be optimised by implementing DSM principles, this will result in the long term savings of costs for the mines involved. The majority of pumping systems found on mines are single shaft systems. Individually these systems have a very high DSM potential. However, if multiple shaft systems can be used for DSM, the benefits will be far greater. Furthermore, combining several sites with an interconnected water pumping system will increase the potential for DSM and enable sites where individually the potential is too low to be feasible for a DSM project to raise their potential. This will result in more sites where DSM projects can be implemented and more clients who can benefit from the DSM programme. The purpose of this study is to investigate and implement a DSM project on an intricate multi-shaft mine pumping system which will be controlled from a single point. The project required a detailed investigation of the pumping systems on each shaft and how the water system is interlinked between the shafts. This project was carried out on Beatrix Mine Shafts 1, 2 and 3. The pumping systems were analysed and simulated according to the specific constraints and requirements that were specified by the mine. During the investigation and implementation of this project, possible efficiency improvements on certain pump stations were discovered and implemented. The improvements enabled both an increase in water flow to the surface and a decrease in power consumption. Due to this load reduction, the savings achieved were higher than those found in most load shifting projects. Moreover, additional infrastructures were installed to ensure communication between pumping systems. Once the simulation and optimisation of the control system was completed, the pumping system network was automated. The load shift resulted in a ± 3.5 MW shift in the morning peak demand period and a ± 6.0 MW shift in the evening peak demand period. This load shift has resulted in an average cost saving of R 80 000 per month during summer tariff period, and R 300 000 per month during winter tariff period. This saving result was calculated by taking load reduction into account. This project has shown that a DSM project can be implemented successfully, given the necessary historical data and expertise, on a pumping system that is interconnected between multiple shafts. / Thesis (M.Ing. (Electrical Engineering))--North-West University, Potchefstroom Campus, 2007.
20

Electricity cost optimisation of a surface potable water pump system / M.P. Slade

Slade, Michael Peter January 2007 (has links)
South Africa is fast approaching an era where its electrical energy demand will surpass the generating capacity of it's primary utility. The reason for this is due to the fact that over the past 10 years, the economic growth in South Africa has increased considerably and has become very energy intensive. South African electrical energy consumption is currently estimated to be growing at a rate of around 1 000 MW per year. Due to the electrical energy demand being the greatest during peak-times, Eskom has introduced various "time of use" tariff structures, such as Megaflex and Ruraflex. These two tariff structures differentiate between standard, peak and off-peak periods of the day, as well as different seasons of the year. The tariffs for these different scenarios are adjusted such that the consumers are persuaded into avoiding unnecessary electrical energy consumption during peak periods. It has been identified that electrical energy consumption can be split into two categories. One of the categories considers sectors where there are a large number of electrical energy consumers, each utilising a negligible amount of power. The other category considers sectors where there are few electrical energy consumers, each utilising large amounts of power. This therefore means that the consumers in the latter category have a great potential in implementing more efficient ways of consuming power. In order to try and control the electrical energy demand problem in South Africa, Eskom has implemented a DSM (Demand Side Management) programme in order to help the larger energy consumers in shifting their peak-time loads to off-peak periods. If the client wishes to shift their load to off-peak periods, Eskom will assist by funding all costs to carry out such a project. According to Eskom's monitoring and verification team, Eskom's DSM initiative has proven to be highly successful. Since the inception of Eskom's DSM programme in 2003, up until the end of 2005, an accumulated total load reduction of 296.3 MW has successfully been realised. At present, most water distribution schemes have been developed without making use of Eskom's DSM initiative. As these schemes consume considerable amounts of electrical energy, they are prime candidates for an initiative such as Eskom's DSM initiative. It had previously been identified that the Vaal Gamagara Water Scheme, situated in Delportshoop, was a prime candidate for Eskom's DSM initiative. Presented in this dissertation are the findings of the DSM investigation. Although the project has yet to be implemented, the proposed intervention methodology was manually tested, where a 3 MW load shift in the evening peak and a 3.6 MW load shift in the morning peak was achieved. If the current intervention methodology is maintained, the annual savings will be in the region of R 830,000.00. / Thesis (M.Ing. (Electrical Engineering))--North-West University, Potchefstroom Campus, 2008.

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