Object Orientation Detection and Correction using Computer Vision

Product validation is a manufacturing step in which a product undergoes safety and functionality tests before it is released. Presently, human labor is used in product validation. Automating product validation can alleviate errors caused during the validation process by human error. However, an impediment to automated product validation is the orientation of the product. It is crucial that a product is correctly oriented before the artificial system can run the quality check. This experiment is designed to address the object orientation problem encountered during the object recognition step of the product validation process. Three techniques were examined to solve the object orientation problem. The first is Principal Component Analysis, and the other two are supervised machine learning techniques: Classification and Regression. The results of the three methods are surveyed, and the limitations of the methods are discussed. The machine learning models are better suited for solving the object-orientation problem in comparison to Principal Component Analysis. The classification model made better predictions twice as often on average than the regression model

Quantitative Risk Evaluation of Obstacle Limitation Surfaces for Final Approaches at Airports

Obstacle limitation surfaces (OLS) are the main safeguard against objects that can pose a hazard to aircraft operations at and around airports. The standard dimensions of the most of those surfaces were estimated using the pilot’s experience at the time when they were included in the standard documents. As a result, some of these standards may have been overestimated, while others may not provide an adequate level of safety. With airports moving to the Safety Management System (SMS) approach to design and operations safety, proper evaluation of the level of safety provided by OLS at specific sites becomes important to airport operators. Therefore, this study attempts to collect actual flight path data using information provided by air traffic control radars and to construct a methodology to assess the probability of aircraft deviating from their approach path. This will be helpful to estimate safe and efficient standard dimensions of the OLS and assess the risk level of objects to the aircraft operations around airports. The methodology is presented using the aircraft trajectories of approaches at Ottawa International Airport (CYOW). Estimated dimensions of Code 3 approach surfaces also are presented

Forgotten exogenous corticosteroid as a cause of central serous chorioretinopathy

Central serous chorioretinopathy (CSCR) is an idiopathic ocular condition – first described in 1866 – that is well known to ophthalmologists. It is less well known to other practitioners. Glucocorticoids have been strongly implicated as a pathogenic factor. We report three patients who developed CSCR following exogenous administration of corticosteroid. Because our patients did not suspect the use of corticosteroid to be important or causative, they did not volunteer the historical detail, and admitted to exogenous corticosteroid injection only with intensive questioning. For their part, physicians should be cognizant of the risk of corticosteroid-induced CSCR, particularly in patients with a prior history of the potentially sight-threatening disease. The development of CSCR is an important iatrogenic and often unrecognized side effect of exogenously administered corticosteroid

Failure of femoral neck fracture fixation in younger patients

Background: Failure of femoral neck fracture fixation in younger patients frequently lead to significant morbidity. This study aims to evaluate the associated risk factors, to help achieve better outcomes.Methods: Records of 25 men and 6 women aged 23 to 50 (mean, 39.8) years who underwent fixation for femoral neck fractures using cancellous screws (n=29), a dynamic hip screw (n=1), or a locking plate (n=1) were reviewed. Patients with or without fixation failure were compared.Results: The mean follow-up period was 28.4 (range, 24–38) months. Of the 31 patients, 24 had bone union and 7 had fixation failure secondary to non-union (n=1), screw cut-out (n=4), and avascular necrosis (n=2). The Revised Trauma Score on admission was 4 in one patient with fixation failure and >6 in all other patients. Comparing patients with or without fixation failure, excess alcohol consumption (5/7 vs. 6/24, p=0.024), smoking (6/7 vs. 9/24, p=0.025), and operative time in minutes (57±16 vs 108±58, p=0.00004), fracture type of OTA 31 B2 or 31 B3 (7/7 vs. 14/24, p=0.027) were significant risk factors.Conclusions: Excess alcohol consumption, smoking, operative time >85 minutes, and displaced fractures were risk factors for femoral neck fixation failure

Associations between dietary profiles and perfluoroalkyl acids in Inuit youth and adults

Background: Perfluoroalkyl acids (PFAAs), a subset of perfluoroalkyl substances (PFAS), are synthetic chemicals used in industrial and consumer applications. They are exceptionally stable and highly mobile in the environment, and were detected in high concentrations in Arctic wildlife and Nunavik Inuit. The study's objective was to study the association between dietary profiles in Nunavik and plasma PFAAs concentrations. Methods: The study used data from the Qanuilirpitaa? 2017 Nunavik Inuit Health Survey (Q2017) (N = 1172) on Inuit adults aged 16-80 years. Nine PFAAs congeners were measured in plasma samples (six were detected). Dietary profiles were identified using latent profile analysis. Two sets of dietary profiles were included; the first included market (store-bought) and country foods (harvested/hunted from the land), and the second included only country foods. Multiple linear regression models regressed log-transformed PFAAs concentrations against the dietary profiles, adjusting for sociodemographic variables. Results: We identified statistically significant 24.54-57.55 % increases in all PFAAs congeners (PFOA, PFNA, PFDA, PFUnDA, PFHxS, and PFOS) in the dietary profile defined by frequent country food consumption compared to the dietary profile defined by frequent market food consumption. Individuals defined by low consumption of foods (related to food insecurity) had higher concentrations of six PFAAs compared to individuals with frequent market food consumption. The associations were stronger with profiles defined by more frequent country food consumption, and particularly those with increased marine mammal consumption. PFDA, PFUnDA, and PFOS were particularly associated with high country food consumption frequency, such that their concentrations increased by approximately 67-83 % compared to those reporting no or very little consumption of any country foods. Conclusions: Increased country food consumption was strongly associated with higher PFAAs concentrations, particularly PFOS, PFDA, and PFUnDA. The results provide further evidence that the quality of country foods is being threatened by PFAAs contamination. Additional national and international regulations are required to protect the Arctic and its inhabitants from these pollutants

Risk factors for a post-operative neutrally aligned total knee arthroplasty in the sagittal plane developing fixed flexion deformity at 2 years follow up study

Background: The incidence of fixed flexion deformity (FFD) following total knee arthroplasty (TKA) has been reported to be as high as 17%, increasing demand on the quadriceps and hindering mobility. The aim of this study is then to identify these predictors for the development of FFD.Methods: In this retrospective study, all patients who underwent primary TKA from January 2008 to June 2009 at a single institution were identified. All patients with neutral alignment in the sagittal place of the knee intra-operatively were identified and followed up. The knee motion was measured in both operated and contralateral knees and followed-up for a minimum of 24 months post-operatively.Results: Multivariate analysis demonstrated pre-operative FFD of the non-operated knee (p-value 0.03), pre-operative range of motion of the operated knee (p-value 0.01) and non-operated (p-value 0.01) knee and pre-operative maximum flexion of the operated knee (p-value 0.001) to be independent risk factors for development of FFD at 24 months.Conclusions: Independent risk factors for the development of post-operative FFD in TKA are pre-operative FFD of the operated knee, FFD of the non-operated knee and the maximum flexion of the operated knee. The relative risk of a male developing FFD is also as high as 1.34