Grinding wheel condition monitoring with boosted classifiers

In this thesis, two data sets collected in grinding process under different cutting and wheel conditions were studied. One is the cutting forces in three directions, i.e. X, Y and Z, collected under two different cutting conditions. The other one is the acoustic emission (AE) signals collected under different wheel conditions(sharp and dull). For the goal of grinding wheel condition monitoring, the regression model with autocorrelated errors was proved to be effective and was used to extract features from signals in this study. The coefficients of the models served as the features used in the classification step that employed boosting method. Based on the AdaBoost and A-boosting algorithms which can only be used in two classes situation, two improved boosting methods called Adaboost-M and A-boosting-M, which can be used to classify multiple classes, are proposed. With the forces data set, we compared Adaboost-M and A-boosting-M against the traditional AdaBoost.M1 and the corresponding weak learners(KNN and Prototype). The accuracies of Adaboost-M and A-boosting-M are higher than that of AdaBoost.M1 and the weak learners in our application. With the AE data set, our focus is to recognize the signals collected when the wheels were dull from the signals collected when the wheels were sharp. The AdaBoost, A-boosting and the corresponding weak learners(KNN and Proto) were used. The results indicate that (i) boosting does not improve the effectiveness of k-nearest neighbor but greatly improve the effectives of the prototype classifier, (ii) depending upon the data, AdaBoost or A-Boosting might produce higher classification accuracy, (iii) the error of false positive is higher than the error of false negative for the better classifiers. Based on the study, the combined use of AR models for feature extraction and boosted algorithms for classification are proved to be a viable approach for grinding wheel condition monitoring

Factors influencing patient willingness to participate in genetic research after a myocardial infarction

Abstract Background Achieving 'personalized medicine' requires enrolling representative cohorts into genetic studies, but patient self-selection may introduce bias. We sought to identify characteristics associated with genetic consent in a myocardial infarction (MI) registry. Methods We assessed correlates of participation in the genetic sub-study of TRIUMPH, a prospective MI registry (n = 4,340) from 24 US hospitals between April 2005 and December 2008. Factors examined included extensive socio-demographics factors, clinical variables, and study site. Predictors of consent were identified using hierarchical modified Poisson regression, adjusting for study site. Variation in consent rates across hospitals were quantified by the median rate ratio (MRR). Results Most subjects consented to donation of their genetic material (n = 3,484; 80%). Participation rates varied greatly between sites, from 40% to 100%. After adjustment for confounding factors, the MRR for hospital was 1.22 (95% confidence interval (CI) 1.11 to 1.29). The only patient-level factors associated with consent were race (RR 0.93 for African Americans versus whites, 95% CI 0.88 to 0.99) and body mass index (RR 1.03 for BMI ≥ 25, 95% CI 1.01 to 1.06). Conclusion Among patients with an MI there were notable differences in genetic consent by study site, but little association with patient-level factors. This suggests that variation in the way information is presented during recruitment, or other site factors, strongly influence patients' decision to participate in genetic studies.Peer Reviewe

Treatment differences by health insurance among outpatients with coronary artery disease

OBJECTIVES: To compare treatment rates by insurance status for 5 quality-of-care indicators for coronary artery disease (CAD) care related to medication treatment. METHOD: Within the NCDR's PINNACLE Registry, we identified 60,814 outpatients with CAD from 30 U.S. practices. Hierarchical modified Poisson regression models with practice site as a random effect were used to study the association between health insurance (no insurance, public or private health insurance) and 5 CAD quality measures. RESULTS: Of 60,814 patients, 5716 (9.4%) patients were uninsured and 11,962 (19.7%) had public insurance, whereas 43,136 (70.9%) were privately insured. After accounting for exclusions, uninsured patients with CAD were 9%, 12%, and 6% less likely to receive treatment with beta-blocker, ACE-I/ARB, and lipid lowering therapy, respectively, than privately insured patients, whereas patients with public insurance were 9% less likely to be prescribed ACE-I/ARB therapy. Most differences by insurance status were attenuated after adjusting for the site providing care. For example, whereas uninsured patients with left ventricular dysfunction and CAD were less likely to receive ACE-I/ARB therapy (unadjusted RR=0.88; 95% CI 0.84-0.93), this difference was eliminated after adjustment for site (adjusted RR=0.95; 95% CI 0.88-1.03; P=0.18). CONCLUSIONS: Within this national outpatient cardiac registry, uninsured patients were less likely to receive evidence-based medications for CAD. These disparities were explained by the site providing care. Efforts to reduce treatment differences by insurance status among cardiac outpatients may additionally need to focus on improving rates of evidence-based treatment at sites with high proportions of uninsured patients

Long‐Term Outcomes Among Elderly Survivors of Out‐of‐Hospital Cardiac Arrest

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/139093/1/jah31396_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139093/2/jah31396.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139093/3/jah31396-sup-0001-SupInfo.pd

Birt-Hogg-Dubé syndrome with c.1579_1580insA variant in a Chinese family: a case report

Birt-Hogg-Dubé (BHD) syndrome, is a rare genetic disease with heterogeneous manifestations in different populations. In this study, we reported a Chinese female BHD case and her family members with c.1579_1580insA variant in FLCN gene, who were characterized by diffused pulmonary cysts/bulla, and reviewed another five familial BHD cases in China. Based on these cases, recurrent spontaneous pneumothorax is likely to be the first symptom for BHD in Chinese patients, with particularly but not limited to c.1579_1580insA variant. Therefore, attention to the early diagnosis of BHD in China should focus on pulmonary signs, but skin or kidney lesions still can not be neglected

Relating the composition of continental margin surface sediments from the Ross Sea to the Amundsen Sea, West Antarctica, to modern environmental conditions

Investigating the multiple proxies involving productivity, organic geochemistry, and trace element (TE) enrichment in surface sediments could be used as paleoenvironment archives to gain insights into past and future environmental conditions changes. We present redox-sensitive TEs (Mn, Ni, Cu, U, P, Mo, Co, V, Zn, and Cd), productivity-related proxies (total organic carbon and opal), and total nitrogen and CaCO3 contents of bulk surface sediments of this area. The productivity proxies from the shelf and coastal regions of the Ross and the Amundsen seas showed that higher productivity was affiliated with an area of nutrient-rich deep water upwelling. The upwelling of weakly corrosive deep water may be beneficial for preserving CaCO3, while highly corrosive dense water, if it forms on the shelf near the coastal region (coastal polynya), could limit the preservation of CaCO3 in modern conditions. There were no oxic or anoxic conditions in the study area, as indicated by the enrichment factors of redox-sensitive TEs (Mn, Co, and U). The enrichment factor of Cd, which is redox-sensitive, indicated suboxic redox conditions in sediment environments because of high primary productivity and organic matter preservation/decomposition. The enrichment factors of other redox-sensitive TEs (P, Ni, Cu, V, and Zn) and the correlations between the element/Ti ratio with productivity and nutrient proxies indicated that the organic matter decomposed, and there was massive burial of phytoplankton biomass. There was variation in the enrichment, such that sediments were enriched in P, Mo, and Zn, but depleted in Ni, Cu, and V