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Auswahl der wissenschaftlichen Literatur zum Thema „Fueling diagnosis“
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Zeitschriftenartikel zum Thema "Fueling diagnosis"
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Maghimbi, Abubakar, Mtebe Majigo, Vincent Mashinji, George Loy und Sekela Mwakyusa. „162 Challenges Fueling the Complexities of TB Diagnosis & TBHIV Comorbidity in Tanzania- IHV experience“. JAIDS Journal of Acquired Immune Deficiency Syndromes 65 (April 2014): 70. http://dx.doi.org/10.1097/01.qai.0000446746.99602.a8.
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Hassannezhad, Reshad. „Hyperketonemia: Clinical features and diagnosis of Diabetic Ketoacidosis“. Endocrinology and Disorders 2, Nr. 5 (27.08.2018): 01–04. http://dx.doi.org/10.31579/2640-1045/033.
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Diets that boost ketone production are increasingly used for treating several neurological disorders. Elevation in ketones in most cases is considered favorable, as they provide energy and are efficient in fueling the body's energy needs.Several physiological and pathological triggers, such as fasting, ketogenic diet, and diabetes cause an accumulation and elevation of circulating ketones. Complications of the brain, kidney, liver, and microvasculature were found to be elevated in diabetic patients who had elevated ketones compared to those diabetics with normal ketone levels. Diabetic ketoacidosis is an acute metabolic complication of diabetes characterized by hyperglycemia, hyperketonemia, and metabolic acidosis. Hyperglycemia causes an osmotic diuresis with significant fluid and electrolyte loss. DKA occurs mostly in type 1 diabetes mellitus (DM). It causes nausea, vomiting, and abdominal pain and can progress to cerebral edema, coma, and death. DKA is diagnosed by detection of hyperketonemia and anion gap metabolic acidosis in the presence of hyperglycemia. Treatment involves volume expansion, insulin replacement, and prevention of hypokalemia. Diabetic ketoacidosis (DKA) is a rare yet potentially fatal hyperglycemic crisis that can occur in patients with both type 1 and 2 diabetes mellitus. Due to its increasing incidence and economic impact related to the treatment and associated morbidity, effective management and prevention is key. Elements of management include making the appropriate diagnosis using current laboratory tools and clinical criteria and coordinating fluid resuscitation, insulin therapy, and electrolyte replacement through feedback obtained from timely patient monitoring and knowledge of resolution criteria. In addition, awareness of special populations such as patients with renal disease presenting with DKA is important. During the DKA therapy, complications may arise and appropriate strategies to prevent these complications are required. DKA prevention strategies including patient and provider education are important. This review aims to provide a brief overview of DKA from its pathophysiology to clinical presentation with in depth focus on up-to-date therapeutic management.
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Sturm, Dominik, Stefan M. Pfister und David T. W. Jones. „Pediatric Gliomas: Current Concepts on Diagnosis, Biology, and Clinical Management“. Journal of Clinical Oncology 35, Nr. 21 (20.07.2017): 2370–77. http://dx.doi.org/10.1200/jco.2017.73.0242.
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Gliomas are the most common CNS tumors in children and adolescents, and they show an extremely broad range of clinical behavior. The majority of pediatric gliomas present as benign, slow-growing lesions classified as grade I or II by the WHO classification of CNS tumors. These pediatric low-grade gliomas (LGGs) are fundamentally different from IDH-mutant LGGs occurring in adults, because they rarely undergo malignant transformation and show excellent overall survival under current treatment strategies. However, a significant fraction of gliomas develop over a short period of time and progress rapidly and are therefore classified as WHO grade III or IV high-grade gliomas (HGGs). Despite all therapeutic efforts, they remain largely incurable, with the most aggressive forms being lethal within months. Thus, the intentions of neurosurgeons, pediatric oncologists, and radiotherapists to improve care for pediatric patients with glioma range from increasing quality of life and preventing long-term sequelae in what is often a chronic, but rarely life-threatening disease (LGG), to uncovering effective treatment options to prolong patient survival in an almost universally fatal setting (HGG). The last decade has seen unprecedented progress in understanding the molecular biology underlying pediatric gliomas, fueling hopes to achieve both goals. Large-scale collaborative studies around the globe have cataloged genomic and epigenomic alterations in gliomas across ages, grades, and histologies. These studies have revealed biologic subgroups characterized by distinct molecular, pathologic, and clinical features, with clear relevance for patient management. In this review, we summarize hallmark discoveries that have expanded our knowledge in pediatric LGGs and HGGs, explain their role in tumor biology, and convey our current concepts on how these findings may be translated into novel therapeutic approaches.
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Perneczky, Robert, und Alexander Kurz. „Dealing with uncertainty: biomarkers for the early detection of Alzheimer's disease“. International Psychogeriatrics 24, Nr. 10 (12.06.2012): 1533–35. http://dx.doi.org/10.1017/s1041610212001056.
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In neuropsychiatric tradition, Alzheimer's disease (AD) is a clinical diagnosis that requires demonstration of a progressive memory-predominant type of dementia and exclusion of alternative causes. This simple set of criteria is neither sensitive for early clinical stages of AD since amnestic dementia only arises when the underlying neurodegeneration is fairly advanced, nor is it specific because it also occurs in other brain disorders involving the medial temporal lobe and cannot be easily distinguished from AD on clinical grounds. Efforts to identify AD before full-blown amnestic dementia develops, i.e. at a prodromal or even asymptomatic stage, and to treat the driving components of the pathology rather than its end products, are fueling the search for diagnostic indicators that unveil the neurodegeneration independently of its typical clinical manifestation. Such indicators are termed biomarkers in current technical parlance.
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Khalifa, Maram, Hassaan B. Aftab und Vitaly Kantorovich. „“Fueling the Fire” - Irish Sea-Moss Resulting in Jod-Basedow Phenomenon in a Patient With Grave’s Disease“. Journal of the Endocrine Society 5, Supplement_1 (01.05.2021): A906. http://dx.doi.org/10.1210/jendso/bvab048.1849.
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Abstract Background: Jod-Basedow phenomenon is a rare cause of thyrotoxicosis due to excess iodine intake. Herbal supplements containing sea-moss have high iodine amount which may precipitate thyrotoxicosis in patients with underlying Grave’s disease or autonomous thyroid nodules. Clinical Case: A seemingly healthy 28-year-old female presented to the ED with chief complaint of fatigue with associated anxiety, palpitations and weight loss. On admission her temperature was 100.4 F, pulse 126 bpm and blood pressure 116/56 mmHg. Exam was unremarkable for thyroid goiter or orbitopathy. Labs revealed WBC count 3.4 x103/µL (ref range 4.0-11.0) with neutropenia, hemoglobin 4.3 g/dL (11.7-15.7), platelet 49 x103/µL (150-450). Liver transaminases (AST, ALT, and alkaline phosphatase) were elevated with levels up to 4 times the upper limit of normal. She was diagnosed with hemolytic anemia secondary to severe Vitamin B12 deficiency due to pernicious anemia. TSH was <0.01 mIU/L (0.27-4.20), free T4 2.46 ng/dL (0.8-1.9) and total T3 139 ng/dL (76-181). The patient subsequently endorsed remote history of hyperthyroidism diagnosed 7 years ago however she could not recall the underlying etiology or the name of medication she was treated with. She reportedly stopped this medication after 1 month due to developing goiter. She also endorsed intermittent use of store-bought supplement of Irish sea moss and bladderwrack in last 2 years. Further workup revealed elevated TSI and TBII antibody titers establishing diagnosis of Grave’s disease. Thyroid ultrasound showed normal sized heterogeneous hypervascular gland with no nodules. I-123 thyroid uptake and scan showed diffuse moderately elevated radioiodine uptake of 16.8% and 40.8% at 4 and 24 hours, respectively. Thionamide therapy was withheld due to concern of neutropenia and transaminitis. She was treated with beta-blocker after which her vital signs normalized. Labs 1 week after stopping sea moss showed TSH 0.01 mIU/L and free T4 1.4 ng/dL. Conclusion: Irish sea moss is a readily available herbal supplement with high, variable amounts of iodine. Despite little scientific evidence, it is often marketed to improve goiter amongst other health benefits. The recommended daily iodine intake per the FDA is 150 mcg. Higher amounts are expected to initially cause a short-lived suppression of thyroid function; the Wolff-Chaikoff effect, followed by “escape” and accelerated production of thyroid hormone in abnormal thyroid gland, known as Jod-Basedow phenomenon. In our case, the patient unknowingly worsened her underlying Grave’s disease due to the Jod-Basedow effect. Of note, apparantly she had a longer than expected course of Wolff-Chaikoff effect preceding the thyrotoxic state due to sporadic irregular intake of sea moss. Discontinuing sea moss led to clinical and biochemical improvement of hyperthyroidism without requiring thionamide therapy.
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Loh, F. Ellen, und Shoshana J. Herzig. „Pain in the United States: Time for a Culture Shift in Expectations, Messaging, and Management“. Journal of Hospital Medicine 14, Nr. 12 (24.07.2019): 787–88. http://dx.doi.org/10.12788/jhm.3277.
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Opioid prescribing has dramatically increased in the United States (US) over the past two decades, fueling the current crisis of opioid-related adverse events and deaths.1 Understanding the potential contributors to this increased prescribing is paramount to developing effective strategies for preventing propagation. In this issue of the Journal of Hospital Medicine, Burden et al. report the results of a cross-sectional observational study investigating the rates of opioid receipt, patient satisfaction with pain control, and other perceptions of pain management in a sample of patients from geographically diverse US hospitals compared with patients hospitalized in seven other countries.2 Although cultural influences on pain perceptions have been demonstrated by others previously, this is the first study to measure opioid receipt and patient satisfaction with pain control across an international sample of hospitalized patients.
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Pierik, Annouk S., C. René Leemans und Ruud H. Brakenhoff. „Resection Margins in Head and Neck Cancer Surgery: An Update of Residual Disease and Field Cancerization“. Cancers 13, Nr. 11 (27.05.2021): 2635. http://dx.doi.org/10.3390/cancers13112635.
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Surgery is one of the mainstays of head and neck cancer treatment, and aims at radical resection of the tumor with 1 cm tumor-free margins to obtain locoregional control. Surgical margins are evaluated by histopathological examination of the resection specimen. It has been long an enigma that approximately 10–30% of surgically treated head and neck cancer patients develop locoregional recurrences even though the resection margins were microscopically tumor-free. However, the origins of these recurrences have been elucidated by a variety of molecular studies. Recurrences arise either from minimal residual disease, cancer cells in the surgical margins that escape detection by the pathologist when examining the specimen, or from precancerous mucosal changes that may remain unnoticed. Head and neck tumors develop in mucosal precursor changes that are sometimes visible but mostly not, fueling research into imaging modalities such as autofluorescence, to improve visualization. Mostly unnoticed, these precancerous changes may stay behind when the tumor is resected, and subsequent malignant progression will cause a local relapse. This led to a clinical trial of autofluorescence-guided surgery, of which the results were reported in 2020. This review focuses on the most recent literature of the improved diagnosis of the resection margins of surgically treated head and neck cancer patients, the pathobiological origin of recurrent disease, and relevant biomarkers to predict local relapse. Directions for further research will be discussed, including potential options for improved and personalized treatment, based on the most recently published data.
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Ahmad, Nura M. R., Cristina Montañola-Sales, Clara Prats, Mustapha Musa, Daniel López und Josep Casanovas-Garcia. „Analyzing Policymaking for Tuberculosis Control in Nigeria“. Complexity 2018 (07.11.2018): 1–13. http://dx.doi.org/10.1155/2018/9253846.
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Today, tuberculosis (TB) is still one of the major threats to humankind, being the first cause of death by an infectious disease worldwide. TB is a communicable chronic disease that every year affects 10 million people and kills almost 2 million people in the world. The main key factors fueling the disease are the progressive urbanization of the population and poverty-related socioeconomic factors. Moreover, the lack of effective tools for TB diagnosis, prevention, and treatment has decisively contributed to the lack of an effective model to predict TB spread. In Nigeria, the rapid urbanization along with unprecedented population growth is causing TB to be endemic. This paper proposes a mathematical model to evaluate TB burden in Nigeria by using data obtained from the local TB control program in the community. This research aims to point out effective strategies that could be used to effectively reduce TB burden and death due to TB in this country at different levels. The study shows that efforts should be oriented to more active case finding rather than increasing the treatment effectiveness only. It also reveals that the persistence of the disease is related to a large number of latently infected individuals and quantifies the lives that could be saved by increasing the notification rate using active case finding strategy. We conclude that undiagnosis is the bottleneck that needs to be overcome in addition to the incorporation, improvement, and/or strengthening of treatment management and other essential TB control measures in Nigeria.
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Pan, Heng, Yanwen Jiang, David Redmond, Kui Nie, Leandro Cerchietti, Rita Shaknovich, Ari M. Melnick, Wayne Tam und Olivier Elemento. „Epigenomic Evolution In Diffuse Large B-Cell Lymphomas“. Blood 122, Nr. 21 (15.11.2013): 634. http://dx.doi.org/10.1182/blood.v122.21.634.634.
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Abstract Diffuse Large B-cell Lymphoma (DLBCL) is the most common non-Hodgkin lymphoma worldwide. It is a heterogeneous disease in which one third of patients either do not respond to treatment or relapse within five years after chemotherapy. It is unclear whether epigenetic alterations are responsible for B cell lymphomas relapse phenotypes, such as increased aggressiveness and chemoresistance. To investigate how the B cell lymphoma epigenome evolves upon chemotherapy, we used Enhanced Reduced Representation Bisulfite Sequencing (ERRBS) to profile DNA methylation genome-wide in primary matched diagnosis-relapse DLBCL samples. We interrogated 13 pairs of DLBCL diagnosis tumors and their matched relapse samples. In addition, we performed methylation profiling of normal tonsilar B cell subsets (Naïve and germinal center B cells) from two healthy human individuals. ERRBS provided DNA methylation levels at 3-4M CpG sites. When combining methylation levels from all interrogated CpG sites, we observed increased DNA methylation levels at CpG-islands (CGIs; p=3.5e-9, t-test) in DLBCLs compared to normal B cells, and stable or slightly decreasing methylation levels outside of CGIs (>10 kb away from known CGIs; p=0.057, t-test). There was no significant change in average DNA methylation levels from diagnosis to relapse either at CGIs or outside of CGIs. However, when we investigated DNA methylation changes at gene promoters, we identified 107 consistently differentially methylated promoters between diagnosis and relapse (> 10% DNA methylation alteration and p < 0.05, paired t-test). Pathway analysis of the corresponding genes using iPAGE identified several pathways and processes associated with either hyper or hypo-methylated genes in relapse, demonstrating that methylation changes associated with relapse are functionally coherent. For example, several genes with TGF-beta receptor activity displayed lower DNA methylation in relapse. Taking advantage of single CpG resolution and high coverage provided by ERRBS, we then sought to investigate the extent of allele-specific methylation (ASM) levels in normal tissues and DLBCL patients. We found increased ASM levels in DLBCLs compared to normal tissues (p=0.0011, t-test) confirming observations in solid tumors. There was no significant change in ASM levels from diagnosis to relapse (p=0.24, t-test). These results suggest that methylation changes associated with lymphomagenesis might frequently involve one allele only, perhaps due to differential nuclear localization of individual chromosomes. However allele-specific methylation may not play a key role in lymphoma progression. Finally, we investigated whether intra-tumor methylation heterogeneity at diagnosis would predict whether a DLBCL patient would relapse. We quantified intra-tumor methylation heterogeneity using a statistical approach based on the probability that two randomly sampled DNA molecules from the tumor cell populations differ from each other in their methylation pattern. We found decreased intra-sample methylation heterogeneity in DLBCLs compared to normal germinal center B cells (p=1.9e-4, t-test), consistent with the clonal origin of tumors. 12 out of 13 pairs also displayed decreased methylation heterogeneity from diagnosis to relapse, which is also consistent with clonal selection upon chemotherapy treatment. We then performed ERRBS on primary tumors from 8 DLBCL patients who have not relapsed five years after treatment. We found that non-relapse patients displayed significantly lower intra-tumor methylation heterogeneity as compared to that of the relapsed patients (p=0.047, t-test), which suggests that increased epigenetic diversity within a population of tumor cells at diagnosis might fuel the Darwinian evolutionary process underlying relapse. We also looked at genetic clonal heterogeneity based on next-generation sequencing of somatic hypermutation profiles in IGH VDJ sequences, but found no differences between relapsed and not relapsed patients (p=0.22, Wilcoxon test). This suggests that epigenetic heterogeneity plays a more substantial role than clonal heterogeneity in fueling the relapse phenotype. In summary, this study provides the first comprehensive characterization of aberrations in DNA methylation in relapse DLBCLs and identified epigenetic diversity in DLBCLs as a potential predictor of relapse. Disclosures: No relevant conflicts of interest to declare.
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Kroshus, Emily, J. D. DeFreese und Zachary Y. Kerr. „Collegiate Athletic Trainers' Knowledge of the Female Athlete Triad and Relative Energy Deficiency in Sport“. Journal of Athletic Training 53, Nr. 1 (01.01.2018): 51–59. http://dx.doi.org/10.4085/1062-6050-52.11.29.
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Context: The female athlete triad (Triad) and relative energy deficiency in sport (RED-S) specify the consequences of energy imbalance. Athletic trainers (ATs) are positioned to identify athletes who are fueling themselves inadequately and experiencing related health and performance consequences. Objective: To assess the knowledge of collegiate ATs about the Triad and RED-S and to examine variability in related screening and referral behaviors among National Collegiate Athletic Association divisions. Design: Cross-sectional study. Setting: Collegiate athletic training departments. Patients or Other Participants: Head ATs at National Collegiate Athletic Association member institutions (n = 285, response rate = 33%). Main Outcome Measure(s): An electronic survey was administered. The number of Triad components that were correctly identified and screening and referral behaviors related to Triad components were measured. Results: Nearly all respondents (98.61% [n = 281]) had heard of the Triad; a smaller proportion (32.98% [n = 94]) had heard of RED-S. On average, respondents correctly identified 2 components of the Triad. We observed differences by sex, with women correctly identifying more components than men (U = 12.426, P = .003). More than half (59.93% [n = 163]) indicated that athletes at their institutions were screened for eating disorders. Nearly three-quarters (70.55% [n = 115]) of respondents indicated that all female athletes at their institutions were screened annually for menstrual dysfunction. More comprehensive referral behaviors for athletes identified as experiencing menstrual dysfunction or a bone injury (eg, athlete referred to a nutritionist, dietitian, or counselor) occurred at Division I institutions than at Division II and III institutions. Conclusions: Continuing education for ATs about the Triad and RED-S may encourage a more comprehensive approach to referral and screening after a diagnosis of menstrual dysfunction or bone-stress injury. Using institutional opportunities, such as preparticipation screening, for identifying components of the Triad or RED-S and specifying protocols for referring athletes who screen positive for 1 of these components should also be explored.
Dissertationen zum Thema "Fueling diagnosis"
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Dufva, Johannes, und Andreas Lindgren. „Machine Learning Models for Fueling Inaccuracy Detection using Gas Exchange Signals in Heavy-duty Vehicle Engines“. Thesis, Uppsala universitet, Avdelningen för systemteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-447180.
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Heavy-duty trucks are important links in the logistic chains of transport. Critical components in trucks include fuel injectors in which inaccuracies can lead to severe financial damage and higher emissions. Intelligent and efficient ways to detect such scenarios are thus of high importance. This thesis applies machine learning algorithms to measured or estimated engine data, focused on gas exchange signals, to detect inaccuracies in fueling quantities. The fueling inaccuracies considered were of low deviations from the nominal curve, with magnitudes not covered by the currently used fueling diagnostics. The data used for the models was generated from Scania test cell engines where different setups of injectors were deliberately set to over- or underfuel. Seven different machine learning models were used on the data and evaluated on how well they could detect deviations from nominal fueling. The tests were mainly done with a pure data-driven approach but also improved through different data selection techniques and using domain knowledge. An investigation to connect the findings within the thesis to real customer data was initiated in order to make the results useful for e.g. predictive maintenance. The complications connected to why this was not ultimately achieved were discussed.
Buchteile zum Thema "Fueling diagnosis"
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Hoffman, Ginger A., und Peter Zachar. „RDoC’s Metaphysical Assumptions: Problems and Promises“. In Extraordinary Science and Psychiatry. The MIT Press, 2017. http://dx.doi.org/10.7551/mitpress/9780262035484.003.0004.
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Critics contend that the categories within the DSM are fueling the current crisis in psychiatry because they are not valid. As a remedy, NIMH has established RDoC, a framework of psychological and behavioral constructs that will — they believe — better guide the search for the biological mechanisms of psychopathology. Here, we assess the ability of RDoC to rescue psychiatry from its crisis, not only by 1) evaluating its promise of increased validity, but 2) recognizing that psychiatric diagnosis can have an impact on patients’ lives independent of its validity. To assess the former, we delineate possible interpretations of validity relevant to psychiatry, and argue that RDoC faces difficult challenges in achieving what is known as etiopathological validity. To assess the latter, we suggest how the very challenge RDoC faces with respect to validity may counterintuitively serve as a benefit to patients, by reducing the extent to which patients reductionistically re-shape their identities.
Konferenzberichte zum Thema "Fueling diagnosis"
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Buehler, Patrick J., Matthew A. Franchek und Imad Makki. „Mass Air Flow Sensor Diagnostics for Adaptive Fueling Control of Internal Combustion Engines“. In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-32023.
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Presented in this paper is an information synthesis (IS) approach for the mass air flow (MAF) sensor diagnosis on internal combustion engines. An information synthesis solution is attractive for diagnostics since the algorithm automatically calibrates itself, reduces the number of false detections and compresses a large amount of engine health information into the model coefficients. There are three primary parts to information synthesis diagnostics. First, an IS model is used to predict the MAF sensor output based on the engine operating condition. The inputs to this IS model include the throttle position sensor (TPS) and the engine speed sensor information. The second part concerns an online adaptation process that is used to reduce the errors between the IS model output and the actual MAF sensor output. Finally the adapted model coefficients are used to diagnose the sensor as well as identify the source for changes in the sensor characteristics. This proposed solution is experimentally tested and validated on a Ford 4.6 L V-8 fuel injected engine. The specific MAF sensor faults to be identified include sensor bias and a leak in the intake manifold.
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Buehler, P. J., M. A. Franchek und I. Makki. „Mass air flow sensor diagnostics for adaptive fueling control of internal combustion engines“. In Proceedings of 2002 American Control Conference. IEEE, 2002. http://dx.doi.org/10.1109/acc.2002.1023940.
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McCarthy, Kieran Joseph, Nerea Panadero, Ioanna Arapoglou, Stephen Kirk Combs, John B. O. Caughman, Eduardo de la Cal, Charles Foust et al. „A Pellet Injector And Associated Plasma Diagnostics For Performing Plasma Studies And Fuelling In The Tj-Ii Stellarator“. In 1st EPS conference on Plasma Diagnostics. Trieste, Italy: Sissa Medialab, 2016. http://dx.doi.org/10.22323/1.240.0134.
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Khosravi, Mahdiar, Jeremy Rochussen, Jeff Yeo, Patrick Kirchen, Gordon McTaggart-Cowan und Ning Wu. „Effect of Fuelling Control Parameters on Combustion Characteristics of Diesel-Ignited Natural Gas Dual-Fuel Combustion in an Optical Engine“. In ASME 2016 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/icef2016-9399.
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Its inherent economic and environmental advantages as an internal combustion engine fuel make natural gas (NG) an attractive alternative to diesel fuel as the primary energy source for some compression ignition (CI) engine applications. Diesel pilot-ignition of NG is an attractive fueling strategy as it typically requires minimal modification of existing CI engines. Furthermore, this strategy makes use of the highly developed direct injection (DI) diesel fuel systems already employed on modern CI engines for to control dual-fuel (DF) combustion. Despite the increasing popularity of the dual-fuel NG engine concept, the fundamental understanding of the fuel conversion mechanisms and the impact of the fueling parameters is still incomplete. A conceptual understanding of the relevant physics is necessary for further development of fueling and pilot-ignition strategies to address the shortcomings of dual-fuel combustion, such as low-load emissions and combustion stability. An experimental facility supporting optical diagnostics via a Bowditch piston arrangement in a 2-litre, single-cylinder research engine (Ricardo Proteus) was used in this study to consider the effect of fueling parameters on the fuel conversion process in a dual fuel engine. Fueling was achieved with port injected CH4 and diesel direct injection using a common rail system. Simultaneous, high-speed natural luminosity (NL) and OH* chemiluminescence imaging was used to characterize dual-fuel combustion and the influence of pilot injection pressure (300 bar vs. 1300 bar) and relative diesel-CH4 ratios (pilot ratio, PR), as these have been noted as key operating dual-fuel control metrics. The pilot injection pressure was observed to have a significant impact on the fuel conversion process. At higher pilot injection pressures, the auto-ignition sites were concentrated around the piston bowl periphery and the reaction zone propagated towards the center of the bowl. At lower pilot injection pressures, ignition initiated in the vicinity of the pilot fuel jet structures and resulted in a more heterogeneous fuel conversion process with regions of intense natural luminosity, attributed to particulate matter. An increase in the pilot ratio (i.e., increased diesel fraction) resulted in a more aggressive combustion event, due to a larger fraction of energy released in a premixed auto-ignition event. This was coupled with a decrease in the fraction of the combustion chamber with significant OH* or NL light emission, indicating incomplete fuel conversion in these regions. The insight to the dual-fuel conversion processes presented in this work will be ultimately used to develop dual-fuel injection strategies, as well as provide much needed validation data for modeling efforts.
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Couso, Daniel, Jose´ Fano, Felicidad Ferna´ndez, Elena Ferna´ndez, Julio A. Guirao, Jose´ L. Lastra, Victor J. Marti´nez, Javier Ordieres und Iva´n Va´zquez. „Development of Codes and Standards for ITER In-Vessel Components“. In ASME 2011 Pressure Vessels and Piping Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/pvp2011-57611.
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This paper describes the changes made to existing version of the Structural Design Criteria for In-vessel Components (SDC-IC) within the ITER project, as a result of the revision and update process carried out recently. Several ITER components, referred to as In-vessel Components, are located inside the ITER Vacuum Vessel: (a) Blanket System: shields the Vessel and Magnets from heat and neutron fluxes; (b) Divertor: extracts heat, helium ash and impurities from the plasma; (c) Fuelling: gas injection system to introduce fuel into the Vacuum Vessel; (d) Ion Cyclotron Heating & Current Drive System: transfers energy to the plasma by electromagnetic radiation; (e) Electron Cyclotron Heating & Current Drive System: uses radio waves to heat to the plasma; (f) Neutral Beam Heating & Current Drive System: accelerates Deuterium particles into the plasma; (g) Lower Hybrid Heating & Current Drive System: drives electric current into the plasma; (h) Diagnostics: measurement systems to control plasma performance, and further understand plasma physics; (i) Test Blankets: demonstrate techniques for ensuring tritium production within the tokamak. ITER In-vessel Components will be subjected to special operating and environmental conditions (neutron radiation, high heat fluxes, electromagnetic forces, etc.). The effects of irradiation on them, including embrittlement, swelling and creep, are not addressed in the existing commercial codes. These conditions are different from conditions in fission reactors and create challenging issues related to the design of these components. For this reason the Structural Design Criteria for ITER In-vessel Components (SDC-IC) [1] was developed for design purposes. SDC-IC was based mainly on the RCC-MR [2] code, and included rules for assessment of effect of neutron irradiation. In 2008 some issues were identified: (1) Some parts had not been fully prepared to cover all needed areas for design; (2) Some important topics needed to be improved; (3) New editions of codes on pressure equipment had been published; (4) No manufacturing rules were included, so consistency between manufacturing rules to be used and design rules in SDC-IC needed to be demonstrated; (5) Compliance with the ESP (French Decree concerning the Pressure Equipment Directive 97/23/EC for non-nuclear pressure vessels) [3] and ESPN (French Order applicable for pressure vessels intended for nuclear facilities) [4] needed to be addressed. The work carried out for Fusion For Energy (European Union’s Joint Undertaking for ITER) is: (a) Modification of design rules, incorporating rules from recently developed codes, and development of specific design rules to cover ITER specific issues and operational conditions; (b) Demonstration of consistency between design rules in SDC-IC and european standards used for manufacturing, in particular EN 13445 [5]; identifying areas where consistency is not provided; (c) Assessment of the compliance with the Essential Safety Requirements of the French Regulations (ESP and ESPN).
Berichte der Organisationen zum Thema "Fueling diagnosis"
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A NEW APPROACH TO HEATING, FUELING, DIAGNOSIS AND CONTROL OF MAGNETIZED PLASMAS, USING NEUTRALIZED ION BEAMS. Office of Scientific and Technical Information (OSTI), Oktober 2011. http://dx.doi.org/10.2172/1025814.
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