In-Line Inspection of Engine Valve Seats Using a Non-Contact Range Sensor

Author(s):  
Vijay Srivatsan ◽  
Bartosz Powałka ◽  
Reuven Katz ◽  
John Agapiou

This paper presents a methodology for the inspection of geometric features on an internal combustion engine valve seat. Inspection of valve seat geometry using a high-precision non-contact range sensor is investigated. A method that can extract the cone angle, the valve seat length and the roundness of the cone surface has been presented. In-line implementation requires a methodology to analyze data from a minimum number of parallel cross sectional profiles of the valve seat. An in-line valve seat inspection prototype machine with two axes of motion that utilizes the method presented in this paper is presented. Validation of the method on several valve seat samples shows a high degree of repeatability, and the results are comparable to coordinate measurement machine measurements of the same samples.

Author(s):  
E. R. Macagno ◽  
C. Levinthal

The optic ganglion of Daphnia Magna, a small crustacean that reproduces parthenogenetically contains about three hundred neurons: 110 neurons in the Lamina or anterior region and about 190 neurons in the Medulla or posterior region. The ganglion lies in the midplane of the organism and shows a high degree of left-right symmetry in its structures. The Lamina neurons form the first projection of the visual output from 176 retinula cells in the compound eye. In order to answer questions about structural invariance under constant genetic background, we have begun to reconstruct in detail the morphology and synaptic connectivity of various neurons in this ganglion from electron micrographs of serial sections (1). The ganglion is sectioned in a dorso-ventra1 direction so as to minimize the cross-sectional area photographed in each section. This area is about 60 μm x 120 μm, and hence most of the ganglion fit in a single 70 mm micrograph at the lowest magnification (685x) available on our Zeiss EM9-S.


2016 ◽  
Vol 57 (3-4) ◽  
pp. 139-154 ◽  
Author(s):  
Laura Schwarz ◽  
Sonia Sippel ◽  
Andrew Entwistle ◽  
Anna Kathrin Hell ◽  
Sarah Koenig

Purpose: Given the high attrition rate in the field of academic surgery, we aimed to characterise the professional and personal situations of female and male academic surgeons as well as to gather data on their respective perceptions of career advancement and work satisfaction. Methods: We conducted a cross-sectional survey in Germany, inviting all identifiable academically highly qualified female surgeons and their male counterparts in a 1:2 ratio to participate. An anonymous 103-item online questionnaire was designed and the data collected between July and September 2014. Results: The questionnaire was sent to 93 female and 200 male surgeons, of whom 63 women (67.7%) and 70 men (35.0%) replied. The average age was 47.5 and 47.1 years, respectively. Respondents identified ‘high degree of expertise', ‘ambition', and ‘clarity of one's professional aims' as important factors affecting professional career development. Both groups felt ‘workload', ‘working hours/shifts', and ‘gender' to be a hindrance, the latter of significantly greater importance to female surgeons. The mean work satisfaction scores were high in both female (69.5%) and male (75.7%) surgeons. The predictors ‘support from superiors' (standardised β coefficient = 0.41) and ‘manual aptitude' (β = 0.41) contributed incrementally to the variance in ‘high degree of work satisfaction' (90-100%) observed for female surgeons. However, childcare provided by ‘kindergarten/crèche/after-school care' had the greatest negative predictive value (β = -1.33). Conclusions: Although there are many parallels, female faculty members experience the culture of academic surgery to some extent differently from their male counterparts, especially when impacted by parenthood and childcare. Faculty development programmes need to develop strategies to improve perceived equality in career opportunities by respecting individuals' requirements as well as offering gender-appropriate career guidance.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Abdelhadi Halawa

Abstract Background Traditional Chinese food has been believed to be closely associated with affecting salubrious health outcomes, enhancing longevity, and interoperating with traditional Chinese medicine. Over the past several decades, traditional Chinese food has been going through significant evolution and qualitative transition of nontraditional eating behaviors. This food transition and eating pattern transformation are propelled by China’s vast population size, rapid socioeconomic development, lifestyle changes, and global influence. Inevitably, these dietary shifts are having a considerable impact not only on public health in China but also globally. Purpose The purpose of the present study is to examine the socioeconomic and health effects of the shift from consuming traditional Chinese food into increasingly consuming Western-style processed foods, fast foods, saturated fats, snacks, sugary beverages, and eating out more often than the traditional home cooking. This study also investigates the prevalence, health effects, and sociodemographic implications of food transition and adopting Western-style eating patterns. Methods Cross-sectional analysis of primary data collected from 1292 adult male and female participants was performed. Participants responded to a cross-sectional self-administered paper-and-pencil-based food history and beverage intake questionnaire. Chi-square analyses were employed to analyze data obtained from the nonparametric variables, whereas t tests were performed to analyze data obtained from the parametric variables. Results There were significant differences in snack food shopping distributions between gender and marital status factors. Females were more likely to purchase more snacks than males, whereas singles were more likely to purchase more snacks than married. Pooled data suggest that 79.67% of the respondents consumed fast food with wide-ranging frequencies. There were significant differences between water and all other typical drinks, as water recorded the highest consumption rate by 65.31%. There were significant differences between the three meal-eating locations, as 48.45% of the respondents were more likely to consume most of their daily meals at home, whereas, combined, 51.55% were more likely to consume most of their daily meals out-of-home. Baking food scored 77.94% compared with all other food preparation methods. Overall healthy eating behaviors results indicated that 49.67% of the respondents consumed a healthy diet most of the time, whereas combined, 50.33% either consumed a healthy diet sometimes or not at all. Conclusions Traditional Chinese eating practices have been transitioning into nontraditional eating behaviors that may be associated with a multitude of chronic non-communicable diseases and high mortality rates. As these rates have been projected to continue rising, there is a need to focus on introducing public health promotion policies, including health education and lifestyle-enhancing initiatives aimed at promoting nutritive balance and adopting healthier eating behaviors. These policies can be tailored to support the most affected groups among the lower- and middle-income Chinese, as well as similar populations in developing countries.


Author(s):  
Jorge L. Ordóñez-Carrasco ◽  
María Sánchez-Castelló ◽  
Elena P. Calandre ◽  
Isabel Cuadrado-Guirado ◽  
Antonio J. Rojas-Tejada

Several studies have emphasized the heterogeneity of fibromyalgia patients. Furthermore, fibromyalgia patients are considered a high-risk suicide group. The ideation-to-action framework proposes a set of transdiagnostic psychological factors involved in the development of suicidal ideation. The present study aims to explore the existence of different subgroups according to their vulnerability to suicidal ideation through these transdiagnostic psychological variables and a set of variables typically associated with fibromyalgia. In this cross-sectional study, 151 fibromyalgia patients were assessed through the Revised Fibromyalgia Impact Questionnaire, Beck Depression Inventory-II, Plutchik Suicide Risk Scale, Interpersonal Needs Questionnaire, Defeat Scale, Entrapment Scale, Psychache Scale, and Beck Hopelessness Scale. A K-means cluster analysis identified two clusters, one (45.70%) according to a low vulnerability, and a second (54.30%) with a high vulnerability to suicidal ideation. These clusters showed statistically significant differences in suicidal ideation and suicide risk. However, no differences were observed in most socio-demographic variables. In conclusion, fibromyalgia patients who present a clinical condition characterized by a moderate-high degree of physical dysfunction, overall disease impact and intensity of fibromyalgia-associated symptoms, along with a high degree of perceived burdensomeness, thwarted belongingness, defeat, entrapment, psychological pain and hopelessness, form a homogeneous group at high risk for suicidal ideation.


2021 ◽  
pp. 192-194
Author(s):  
Shazia Bashir ◽  
Aamir Hussain ◽  
Irm Yasmeen

AIM: To evaluate and compare the cytograding of breast cancers using Robinson's and Moriquand's grading methods MATERIAL AND METHODS: This study was a cross-sectional retrospective study conducted over a period of three years w. e .f October 2014 to October 2017 and includes diagnosed or highly suspicious malignant cases of breast carcinoma. Slides were retrieved from the cytology section of Department of Pathology, GMC Jammu. A total of 84 cases of breast cancers were studied and grading was done using Robinson's and Mouriquand's methods and the two grading methods were then compared. RESULTS: Out of 84 cases of breast cancers , on using Robinson's grading method , 11 cases [13.10%] were graded as grade 1, 65 cases [77.38%] were graded as grade 2 and 8 cases [9.52%] cases as grade 3. 9 (10.71%) cases are graded as Grade I by Mouriquand's method with score less than 5. 68(80.95%) cases were graded as Grade II with score 5-9 and 7 (8.33%) were graded ad Grade III with score ≥10. On doing comparison between the two cytograding methods, we found a high degree of concordance between the two systems [ 96.42% ] . The relationship observed between the scores obtained by the two methods was also seen to be highly signicant. CONCLUSION: There is possibility of comprehensive cytograding of breast cancers by using the two different methods proposed by Robinson's and Moriquand's but out of the two methods inspite of a high degree of concordance between the two methods , the grading system of Robinson's because of its more objective set of criterias and easy reproducibility has been found to be easier and better.


2021 ◽  
Vol 15 (10) ◽  
pp. 2619-2621
Author(s):  
Mariya Manzoor ◽  
Haseeb Ahmed Khan ◽  
Sabiha Riaz ◽  
Imrana Tanvir ◽  
Atiya Batool Gardezi ◽  
...  

Aim: To determine the degree of agreement between Ki67 and histopathology to differentiate between hydatidiform mole and hydropic abortus. Methods: Descriptive, Cross Sectional Survey was conducted in the Department of Pathology, Fatima Memorial Hospital, Lahore during 6 months (May 11, 2016 to Nov 11, 2016). Using non-probability consecutive sampling, 105 cases were included in this study as per the inclusion and exclusion criteria. 10% buffered formalin was used to fix the sepecimens. Gross examination and staining with Hematoxylin and Eosin was done. The cases were diagnosed by a histopathologist. IHC staining Ki67 was performed, assessed by histopathologist and the data was recorded on the proforma. Results: The mean age was 27.79±5.81 years with minimum and maximum ages of 18 years and 42 years respectively. The histopathological findings showed hydatidiform mole in 41 (39%) women and hydropic abortus in 64(61%) women. The Ki67 was reported to be >25 in 41(39%) patients and less than or equal to 25 in 64(61%) patients. The agreement of differentiation in the two types for histopathology and Ki67 was found in 101(96.2%) patients. Kappa statistics showed 92% (p-value= 0.000) strength of agreement between histopathology and Ki67. Conclusion: There is high degree of agreement between Ki67 and histopathology for differentiation of hydatidiform mole and hydropic abortus. So Ki67 can be used as an adjacent in histopathologic diagnosis of hydatidiform mole in difficult cases. MeSh words: Hydatidiform Mole, Immunohistochemistry, Ki-67 Antigen


2021 ◽  
Vol 903 ◽  
pp. 79-89
Author(s):  
R. Sundara Rao ◽  
K. Hemachandra Reddy ◽  
Ch.R. Vikram Kumar

In an internal combustion engine poppet valve is the crucial component which often opens and closes, thereby regulating gas flow in an engine cylinder. During engine operation, the valve is exposed to high temperature gases (thermal load) along with spring and cam loads (mechanical load). Due to high temperatures and fatigue loads, the valves are subjected to metallurgical changes and leads to failure. In order to resist these extreme conditions of high temperature and mechanical loads, the engine valve should possess special properties such as high surface hardness, a good amount of thermal conductivity, and fatigue strength. In this work, the reasons for the failure of two wheeler engine valve were evaluated and found that failure takes place due to change in the chemical composition mainly due to thermal diffusion at the interfaces. Thermal barrier coatings on the valve surface arrest the temperature load and increase its life. In this work, the performance of various titanium based composite coatings, i.e., TiN, TiC, TiC-Al2O3, TiCN, TiAlN, TiN- Al2O3, DLC, and uncoated valves of two wheeler engine was simulated using Finite Element Analysis. The simulation results indicated that coated valves have less thermal and fatigue loading and have more life than the uncoated valve. The Finite element simulation results of both coated and uncoated valves are presented and analyzed in this paper.


1989 ◽  
Author(s):  
R. van Diesel ◽  
G. C. Barber ◽  
J. M. Larson ◽  
S. L. Narasimhan
Keyword(s):  

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