Autonomic computing holds great promise for software systems of the future, but at the same time poses great challenges for Software Engineering. Autonomic computing research aims to design software systems that self-configure, self-repair, self-optimize and self-protect, so as to reduce software maintenance cost while improving performance. The aim of our research is to develop tool-supported methodologies for designing and operating autonomic systems. Like other researchers in this area, we assume that autonomic system architectures consist of monitoring, analysis/diagnosis, planning, and execution components that define a feedback loop and serve as the basis for system self-management. This thesis proposes an autonomic framework founded on models of requirements and design. This framework defines the normal operation of a software system in terms of models of its requirements (goal models) and/or operation (statechart models). These models determine what to monitor and how to interpret log data in order to diagnose failures. The monitoring component collects and manages log data. The diagnostic component analyzes log data, identifies failures, and pinpoints problematic components. We transform the diagnostic problem into a propositional satisfiability (SAT) problem solvable by off-the-shelf SAT solvers. Log data are preprocessed into a compact propositional encoding that scales well with growing problem size. For repair, our compensation component executes compensation actions to restore the system to an earlier consistent state. The framework repairs failures through reconfiguration when monitoring and diagnosis use requirements. The reconfiguration component selects a best system reconfiguration that contributes most positively to the system's non-functional requirements. It selects a reconfiguration that achieves this while reconfiguring the system minimally. The framework does not currently offer a repair mechanism when monitoring and diagnosis use statecharts. We illustrate our framework with two medium-sized, publicly-available case studies. We evaluate the framework's performance through a series of experiments on randomly generated and progressively larger specifications. The results demonstrate that our approach scales well with problem size, and can be applied to industrial sized software applications.

The current maxim concerning diagnosis and treatment of mood and anxiety disorders is that family physicians fail to appropriately respond to patients with anxiety and depression. This estimate is based upon a collection of studies that have found that accurate recognition in general practice occurred in 9% to 75% of patients with depression, and 34% to 50% of patients with anxiety. However, most studies have found that more than half of physicians accurately detected depression and anxiety in their patients.<p> This dissertation examined physicians responses (detection, treatment, and follow-up) to clinical scenarios of patients presenting with symptoms of either depression or anxiety. Furthermore, this study evaluated the associations between physicians responses and physician attributes (personal and professional), organizational setting, information/resource use, and barriers to care.<p> A cross-sectional study of Saskatchewan family physicians yielded a response rate of 49.7% (N=331/666). The results of this study revealed that most physicians provided appropriate depression and anxiety care with respect to recognition of disorders and follow-up care. Specifically, 85.4% of physicians provided an accurate tentative diagnosis of depression, and 86.3% provided an accurate tentative diagnosis of anxiety; 82.5% of physicians suggested adequate follow-up depression care while 79.4% offered adequate follow-up anxiety care. However, a notable proportion of physicians did not provide effective treatment; 65.6% of physicians recommended effective (immediate) anxiety treatment, and 55.6% recommended effective (immediate) depression treatment.<p> This study found that physicians provision of care to patients with anxiety and depression was more likely to be associated with their personal attributes, organizational setting, and information/resource use than with their professional attributes. First, neither tentative diagnosis of depression nor tentative diagnosis of anxiety was significiantly associated with any of the tested measures. Second, ineffective treatment of depression was significantly more likely among physicians who were female, educated at the undergraduate level in Canada (versus elsewhere), scored lower on anxiety attitude factor 1 (social context view of anxiety amenable to intervention), had a low patient load (< 100 patients/week), and used medical textbooks to make specific clinical decisions; ineffective treatment of anxiety was significantly more likely among physicians who had completed their undergraduate and postgraduate medical training in Canada (versus elsewhere), had a low patient load ( <100 patients/week), did not practice in a private office/clinic, and used colleagues within as well as outside their main patient care setting to update their general medical knowledge. Third, physicians were significantly more likely to provide inadequate follow-up care to the depressed patient if they were in solo practice and used drug manuals to update their general medical knowledge, and significantly more likely to provide inadequate follow-up care to the anxious patient if they (the physician) were female and did not use mental health professionals to update their general medical knowledge.<p> Results indicated that after controlling for the effects of other factors, physicians with low patient loads were three times more likely to provide ineffective treatment of depression than physicians with high patient loads. Furthermore, when holding the effects of all other factors constant, physicians who had completed postgraduate training in Canada were approximately five times more likely to provide ineffective treatment of the anxious patient than physicians who had completed their postgraduate training outside of Canada.

Autonomic computing holds great promise for software systems of the future, but at the same time poses great challenges for Software Engineering. Autonomic computing research aims to design software systems that self-configure, self-repair, self-optimize and self-protect, so as to reduce software maintenance cost while improving performance. The aim of our research is to develop tool-supported methodologies for designing and operating autonomic systems. Like other researchers in this area, we assume that autonomic system architectures consist of monitoring, analysis/diagnosis, planning, and execution components that define a feedback loop and serve as the basis for system self-management. This thesis proposes an autonomic framework founded on models of requirements and design. This framework defines the normal operation of a software system in terms of models of its requirements (goal models) and/or operation (statechart models). These models determine what to monitor and how to interpret log data in order to diagnose failures. The monitoring component collects and manages log data. The diagnostic component analyzes log data, identifies failures, and pinpoints problematic components. We transform the diagnostic problem into a propositional satisfiability (SAT) problem solvable by off-the-shelf SAT solvers. Log data are preprocessed into a compact propositional encoding that scales well with growing problem size. For repair, our compensation component executes compensation actions to restore the system to an earlier consistent state. The framework repairs failures through reconfiguration when monitoring and diagnosis use requirements. The reconfiguration component selects a best system reconfiguration that contributes most positively to the system's non-functional requirements. It selects a reconfiguration that achieves this while reconfiguring the system minimally. The framework does not currently offer a repair mechanism when monitoring and diagnosis use statecharts. We illustrate our framework with two medium-sized, publicly-available case studies. We evaluate the framework's performance through a series of experiments on randomly generated and progressively larger specifications. The results demonstrate that our approach scales well with problem size, and can be applied to industrial sized software applications.

Electrical machines are subject to different types of failures. Early detection of the incipient faults and fast maintenance may prevent costly consequences. Fault diagnosis of wind turbine is especially important because they are situated at extremely high towers and therefore inaccessible. For offshore plants, bad weather can prevent any repair actions for several weeks. In some of the new wind turbines synchronous generators are used and directly connected to the grid without the need of power converters. Despite intensive research efforts directed at rotor fault diagnosis in induction machines, the research work pertinent to damper winding failure of synchronous machines is very limited. This dissertation is concerned with the in-depth study of damper winding failure and its traceable symptoms in different machine signals and parameters. First, a model of a synchronous machine with damper winding based on the winding function approach is presented. Next, simulation and experimental results are presented and discussed. A specially designed inside-out synchronous machine with a damper winding is employed for the experimental setup. Finally, a novel analytical method is developed to predict the behavior of the left sideband amplitude for different numbers and locations of the broken bars. This analysis is based on the magnetic field theory and the unbalanced multiphase circuits. It is found that due to the asymmetrical structure of damper winding, the left sideband component in the stator current spectrum of the synchronous machine during steady state asynchronous operation is not similar to that of the induction machine with broken bars. As a result, the motor current signature analysis (MCSA) for detection rotor failures in the induction machine is usable to detect broken damper bars in synchronous machines. However, a novel intelligent-systems based approach is developed that can identify the severity of the damper winding failure. This approach potentially can be used in a non-invasive condition monitoring system to monitor the deterioration of a synchronous motor damper winding as the number of broken bars increase over time. Some other informative features such as speed spectrum, transient time, torque-speed curve and rotor slip are also found for damper winding diagnosis.

Les dimensions dels transistors disminueixen per a cada nova tecnologia CMOS. Aquest alt nivell d'integració complica el procés de fabricació dels circuits integrats, apareixent nous mecanismes de fallada. En aquest sentit, els mètodes de diagnosi actuals no són capaços d'assumir els nous reptes que sorgeixen per a les tecnologies nanomètriques. A més, la inspecció física de fallades (Failure Analysis) no es pot aplicar des d'un bon començament, ja que els costos de la seva utilització són massa alts. Per aquesta raó, conèixer el comportament dels defectes i dels seus mecanismes de fallada és imprescindible per al desenvolupament de noves metodologies de diagnosi que puguin superar aquests nous reptes. En aquest context, aquesta tesi presenta l'anàlisi dels mecanismes de fallada i proposa noves metodologies de diagnosi per millorar la localització de ponts (bridge) i oberts (open). Per a la diagnosi de ponts, alguns treballs s'han beneficiat de la informació obtinguda durant el test de corrent (IDDQ). No obstant no han tingut en compte l'impacte del corrent de dowsntream. Per aquesta raó, en aquesta tesi s'analitza l'impacte d'aquest corrent degut als ponts i la seva dependència amb la tensió d'alimentació (VDD). A més, es presenta una nova metodologia de diagnosi basada en els múltiples nivells de corrent. Aquesta tècnica considera els corrents generats per les diferents xarxes connectades pel pont. Aquesta metodologia s'ha aplicat amb èxit a un conjunt de xips defectuosos de tecnologies de 0.18 µm i 90 nm.Com alternativa a les tècniques basades en corrent, els shmoo plots també poden ser útils per a la diagnosi. Tradicionalment s'ha considerat que valors baixos de VDD són més apropiats per a la detecció de ponts. Tanmateix es demostra en aquesta tesi que en presència de ponts connectant xarxes equilibrades, valors alts de VDD són fins i tot més apropiats que tensions baixes, amb la conseqüent implicació que això té per a la diagnosi.En relació als oberts, s'ha dissenyat i fabricat un xip amb la inclusió intencionada d'oberts complets (full opens) i oberts resistius. Experiments fets amb els xips demostren l'impacte de les capacitats d'acoblament de les línies veïnes. A més, pels oberts resistius s'ha comprovat la influència de l'efecte història i de la localització de l'obert en el retard. Tradicionalment s'ha considerat que el retard màxim s'obté quan un obert resistiu es troba al principi de la línia. No obstant això no es pot generalitzar a oberts poc resistius, ja que en aquests casos es demostra que el màxim retard s'obté per a una localització intermèdia. A partir dels resultats experimentals obtinguts amb el xip, s'ha desenvolupat una nova metodologia per a la diagnosi d'oberts complets a les línies d'interconnexió. Aquest mètode divideix la línia en diferents segments segons la informació de layout de la pròpia línia. Aleshores coneixent els valors de les línies veïnes, es prediu la tensió del node flotant, la qual es compara amb el resultat experimental obtingut a la màquina de test. Aquest mètode s'ha aplicat amb èxit a un seguit de xips defectuosos pertanyents a una tecnologia de 0.18 µm.Finalment, s'ha analitzat l'impacte que tenen els corrents de túnel a través del terminal de porta en presència d'un obert complet. Com les dimensions disminueixen per a cada nova tecnologia, l'òxid de porta és suficientment prim com per generar corrents de túnel que influencien el node flotant. Aquests corrents generen una evolució temporal al node flotant fins fer-lo arribar a un estat quiescent, el qual depèn de la tecnologia. Es comprova que aquestes evolucions temporals són de l'ordre de segons per a una tecnologia de 0.18 µm. Tanmateix les simulacions demostren que aquests temps disminueixen fins a uns quants µs per a tecnologies futures. Degut a l'impacte dels corrents de túnel, un seguit d'oberts complets s'han diagnosticat en xips de 0.18 µm. / Transistor dimensions are scaled down for every new CMOS technology. Such high level of integration has increased the complexity of the Integrated Circuits (ICs) manufacturing process, arising new complex failure mechanisms. However, present diagnosis methodologies cannot afford the challenges arisen for future technologies. Furthermore, physical failure analysis, although indispensable, is not feasible on its own, since it requires high cost equipment, tools and qualified personnel. For this reason, a detailed understanding and knowledge of defect behaviours is a key factor for the development of improved diagnosed methodologies to overcome the challenges of nanometer technologies. In this context, this thesis presents the analysis of existing and new failure mechanisms and proposed new diagnosis methodologies to improve the diagnosis of faults, focused on bridging and open faults.IDDQ is a well known technique for the diagnosis of bridging faults. However, previous works have not considered the impact of the downstream current for the diagnosis of such faults. In this thesis, the impact and the dependence of the downstream current with the power supply voltage (VDD) is analyzed and experimentally measured. Furthermore, a multiple level IDDQ based diagnosis technique is presented. This method takes benefit from the currents generated by the different network excitations. This technique is successfully applied to real defective devices from 0.18 µm and 90 nm technologies.As an alternative to current based techniques, shmoo plots can be also useful for diagnosis purposes. Low voltage has been traditionally considered as an advantageous condition for the detection of bridging faults. However, it is demonstrated that in presence of bridges connecting balanced n- and p-networks, high VDD values are also advantageous for the detection of bridges, which has its direct translation into diagnosis application. Experimental evidence of this fact is presented.Related to open faults, an experimental chip has been designed and fabricated in a 0.35 µm technology, where full and resistive open defects have been intentionally added. Different experiments have been carried out so that the impact of the neighbouring coupling capacitances has been quantified. Furthermore, for resistive opens, experiments have demonstrated the influence of the history effect and the location of the defect on the delay. Traditionally, it has been reported that the highest delay is obtained when the resistive open is located at the beginning of the net. Nevertheless, this thesis demonstrates that this is not true for low resistive open, since the highest delay is obtained for an intermediate location. Experimental measurements prove this behaviour.Derived from the results obtained with the fabricated chip, a new methodology for the diagnosis of interconnect full open defects is developed. The FOS (Full Open Segment) method divides the interconnect line into different segments based on the topology of the faulty line. Knowing the logic state of the neighbouring lines, the floating net voltage is predicted and compared with the experimental results obtained on the tester. This method has been successfully applied to a set of 0.18 µm defective devices. Finally, the impact of the gate tunnelling leakage currents on the behaviour of full open defects has also been analyzed. As technology dimensions are scaled down, the oxide thickness is thin enough so that the gate tunnelling leakage currents influence the behaviour of floating lines. They cause transient evolutions on the floating node until reaching the steady state, which is technology dependent. It is experimentally demonstrated that these evolutions are in the order of seconds for a 0.18µm technology. However, for future technologies, simulations show that the evolutions decrease down to a few µs. Based on this factor, some full open faults present in 0.18 µm technology devices are diagnosed.

Early diagnosis of HIV in infants is critical because it can remarkably impact an infant’s survival. DNA PCR is the standard test for diagnosis of HIV-1 in infants and young children less than 18 months of age. For settings that lack the adequate infrastructure for processing whole blood and cold-chain transportation, the collection of dried blood spots (DBS) has facilitated the detection of HIV-1 in infants as early as 4-6 weeks after birth. Molecular testing using DBS provides an accurate method for the identification of HIV-1 but quality testing depends greatly on adequate quality assurance. A voluntary, cost-free external quality assurance program established by the U.S. Centers for Disease Control and Prevention, Global AIDS Program was implemented to monitor the performance of laboratories conducting HIV EID from DBS in an effort to provide the critically needed external quality assurance measures in resource-constrained settings. Known HIV- positive and negative DBS specimens to be used as internal controls and ten blinded DBS specimens are shipped internationally tri-annually with a 30 day testing result turnaround. Peer comparison is provided after each testing time point. Advances by resource-constrained countries to conduct EID have resulted in more children being tested, which resulted in enrollment and participation expanding significantly to include greater than 104 laboratories from 36 countries. Mean test scores have improved with each testing but false negative results are twice as likely as false positive discordant outcomes.

Diagnosis and Supervision of technical systems is used to detect  faults when they occur. To make a diagnosis, tests based on residuals can be used. Residuals are used to compare observations of  the system with a model of the system, to detect inconsistencies. There are often many different types of faults which affects the  state of the system. These states are modeled as fault modes. The  difference between fault modes are the presence of faults in the  model. For each fault mode a different set of model equations is  used to describe the behaviour of the real system. When doing fault  diagnosis in real time it is good, and sometimes vital, to be able to change fault mode of the model, when a fault suddenly occurs in the real system. If multiple faults can occur the number of  combinations of faults is often so big, even for relatively small  systems, that residuals for all fault modes can not be prepared. To  handle this problem, the residuals are to be generated when they are  needed. The main task in this thesis has been to investigate how residuals  can be automatically generated, given a fault mode with a  corresponding model. An algorithm has been developed and to verify  the algorithm a model of a satellite power system, called  ADAPT-Lite, has been used. The algorithm has been made in two versions. One is focusing on numerical calculations and the other is  allowing algebraical calculations. A numerical algorithm is preferred in an automatized process because  of generally shorter calculation times and the possibility to apply it to systems which can not be solved algebraically but the  algebraical algorithm gives slightly more accurate results in some  cases. / Diagnos och övervakning av tekniska system används för att upptäcka fel när de inträffar. För att ställa en diagnos kan tester baserade på residualer användas. Residualer används för att jämföra observationer av ett system med en model av system för att upptäcka inkonsistens. Det finns ofta många typer av fel som påverkar ett systems tillstånd.Dessa tillstånd modelleras med olika felmoder. För varje felmod används olika uppsättningar av modellekvationer för att beskriva systemets beteende. När diagnoser ska ställas i realtid är det ofta bra och ibland avgörande att kunna byta felmod när ett fel plötsligt inträffar i systemet. Om multipelfel kan inträffa blir antalet kombinationer av fel ofta så stort att residualekvationerna för alla felmoder inte kan förberedas. Detta gäller även för relativt små system. För att hantera problemet bör residualerna kunna genereras vid den tidpunkt då de behövs. Examensarbetets huvuduppgift handlar om att undersöka hur residualerna kan genereras automatiskt, givet en felmod och en modell. En algoritm har utvecklats och verifierats med en model av ett kraftsystem för en satellit, kallad ADAPT-Lite. Algoritmen har gjorts i två versioner. Den ena tillåts göra algebraiska beräkningar men den andra, i så storutsträckning som möjligt, tillåts endast göra numeriska beräkningar. En numerisk algoritm föredras i en automatiserad process p.g.a. generellt sett kortare beräkningstid och dess egenskap att kunna lösa vissa problem som inte kan lösas algebraiskt. Den algebraiska algoritmen har dock visats sig ge aningen noggrannare resultat i många fall.

The purpose of a heat pump is to control the temperature of an enclosed space. This is done by using heat exchange with a heat source, for example water, air, or ground. In the air source heat pump that has been studied during this master thesis, a refrigerant exchanges heat with the outdoor air and with a water distribution system. The heat pump is controlled through the circuit containing the refrigerant and it is therefore crucial that this circuit is functional. To ensure this, a diagnosis system has been created, to be able to detect and isolate sensor errors. The diagnosis system is based on mathematical models of the refrigerant circuit with its main components: a compressor, an expansion valve, a plate heat exchanger, an air heat exchanger, and a four-way valve. Data has been collected from temperature- and pressure sensors on an air source heat pump. The data has then been divided into data for model estimation and data for model validation. The models are used to create test quantities, which in turn are used by a diagnosis algorithm to determine whether an error has occurred or not. There are nine temperature sensors and two pressure sensors on the studied air source heat pump. Four fault modes have been investigated for each sensor: Stuck, Offset, Short circuit and Open circuit. The designed diagnosis system is able to detect all of the investigated error modes and isolate 40 out of 44 single errors. However, there is room for improvement by constructing more test quantities to detect errors and decouple more fault modes. To further develop the diagnosis system, the existing models can be improved and new models can be created.

Rheumatoid Arthritis (RA) is a chronic autoimmune disease that affects 0,5-1% of the general population worldwide. The disease is a complex genetic disease, meaning that several genes, environmental factors and stochastic factors act as players in the development of the disease. RA causes inflammation in the joints typically in the hands and feet. It also can affect surrounding tissue and organs in the body. RA affects mostly women in their middle age, but the disease can occur at every age and in both genders. New research indicates that early treatment can improve quality of life and living conditions for the patients since medical treatment of the disease can cause remission.   Thermo Fischer Scientific ImmunoDiagnostic Division in Uppsala started the development of a new diagnostic tool, ISAC, to provide early diagnosis for RA patients and consequently enable early treatment.   The report will discuss the costs associated with the disease today and in connection to diagnosis, medication, hospital admissions and sick leave in Sweden. This will lead to a discussion and presentation of a market strategy for the first phase of the introducing the product. The results from the latest study done with ISAC shows that ISAC is “as good as” the present and competitive diagnostic method such as ELISA/CCP2 tests but ISAC has the ability to diagnose 18% more patients. Early diagnosis allows cost savings and during year 4 and with patient base of 3600 patients the savings are 154 million SEK or more for the healthcare system. From the selected group of patients around 900 new patients will be added annually.   The associated cost savings for the healthcare system can be up to 25% for each patient compared to present methods. In addition, there is a great value for each additional year of working life for the patient. However this added value is extremely difficult to predict.

The current maxim concerning diagnosis and treatment of mood and anxiety disorders is that family physicians fail to appropriately respond to patients with anxiety and depression. This estimate is based upon a collection of studies that have found that accurate recognition in general practice occurred in 9% to 75% of patients with depression, and 34% to 50% of patients with anxiety. However, most studies have found that more than half of physicians accurately detected depression and anxiety in their patients.<p> This dissertation examined physicians responses (detection, treatment, and follow-up) to clinical scenarios of patients presenting with symptoms of either depression or anxiety. Furthermore, this study evaluated the associations between physicians responses and physician attributes (personal and professional), organizational setting, information/resource use, and barriers to care.<p> A cross-sectional study of Saskatchewan family physicians yielded a response rate of 49.7% (N=331/666). The results of this study revealed that most physicians provided appropriate depression and anxiety care with respect to recognition of disorders and follow-up care. Specifically, 85.4% of physicians provided an accurate tentative diagnosis of depression, and 86.3% provided an accurate tentative diagnosis of anxiety; 82.5% of physicians suggested adequate follow-up depression care while 79.4% offered adequate follow-up anxiety care. However, a notable proportion of physicians did not provide effective treatment; 65.6% of physicians recommended effective (immediate) anxiety treatment, and 55.6% recommended effective (immediate) depression treatment.<p> This study found that physicians provision of care to patients with anxiety and depression was more likely to be associated with their personal attributes, organizational setting, and information/resource use than with their professional attributes. First, neither tentative diagnosis of depression nor tentative diagnosis of anxiety was significiantly associated with any of the tested measures. Second, ineffective treatment of depression was significantly more likely among physicians who were female, educated at the undergraduate level in Canada (versus elsewhere), scored lower on anxiety attitude factor 1 (social context view of anxiety amenable to intervention), had a low patient load (< 100 patients/week), and used medical textbooks to make specific clinical decisions; ineffective treatment of anxiety was significantly more likely among physicians who had completed their undergraduate and postgraduate medical training in Canada (versus elsewhere), had a low patient load ( <100 patients/week), did not practice in a private office/clinic, and used colleagues within as well as outside their main patient care setting to update their general medical knowledge. Third, physicians were significantly more likely to provide inadequate follow-up care to the depressed patient if they were in solo practice and used drug manuals to update their general medical knowledge, and significantly more likely to provide inadequate follow-up care to the anxious patient if they (the physician) were female and did not use mental health professionals to update their general medical knowledge.<p> Results indicated that after controlling for the effects of other factors, physicians with low patient loads were three times more likely to provide ineffective treatment of depression than physicians with high patient loads. Furthermore, when holding the effects of all other factors constant, physicians who had completed postgraduate training in Canada were approximately five times more likely to provide ineffective treatment of the anxious patient than physicians who had completed their postgraduate training outside of Canada.