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1.
Environ Sci Pollut Res Int ; 30(10): 27539-27559, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36383312

ABSTRACT

Aviation emissions originated from the fuel burn have been hot topics by engineers and policy-makers due to their harmful effects on the environment and thereby human health as well as sustainability. In this study, it is tried that several emission indexes (EIs) involving CO, HC and NOx as well as fuel flow of several commercial aircraft engines (CAEs) are predicted using support vector regression (SVR) and long short-term memory (LSTM) approaches for take-off phase. Moreover, exergo-environmental parameters involving exergy efficiency (ExEFF), wasted exergy ratio (WExR) and environmental effect factor (EEF) pertinent to CAEs are computed employing thermodynamics laws. While establishing the models, rated thrust, by-pass ratio, overall pressure ratio and combustion type of the CAEs are utilized as the model inputs. According to the findings of emission modelling, the coefficient of determination (R2) of EI NOx and EI CO of the CAEs is found as 0.929074 and 0.960277 with SVR, whereas their R2 values are elevated to 0.954878 and 0.989283 with LSTM approach, respectively. However, R2 of EI HC is determined lower with 0.632280 (by SVR) and 0.651749 (by LSTM). On the other hand, exergo-environmental parameters for the CAEs are estimated with high correctness at both models. Namely, R2 of ExEFF and EEF regarding the CAEs are computed as 0.991748 and 0.989067 by SVR; however, these are calculated as 0.994785 and 0.992797 by LSTM method. To model these parameters with low error by using significant design variables as model inputs could help in predicting emission and environmental metrics for new engine designs.


Subject(s)
Air Pollutants , Deep Learning , Humans , Air Pollutants/analysis , Vehicle Emissions/analysis , Aircraft , Climate
2.
Turk Pediatri Ars ; 55(2): 124-130, 2020.
Article in English | MEDLINE | ID: mdl-32684757

ABSTRACT

AIM: The quadriceps angle is the angle between the line drawn from the spina iliaca anterior superior to the midpoint of the patella, and the line drawn from the midpoint of the patella to the tuberositas tibiae. It is important for lower extremity posture. The aim of this study was to determine the normative quadriceps angle value by measurement, and to assess the probable effect of factors such as measurement position, age, sex, and presence of pes planus on these values. MATERIAL AND METHODS: A total of 599 children consisting of 296 (49.4%) girls and 303 (50.6%) boys aged between 2 and 8 years, were included in the study. The children were divided into three groups by age as 2-4 years, 4-6 years, and 6-8-years. After the children's demographic data were collected, the quadriceps angle was measured using an electronic goniometer. Pes planus was assessed by drawing the Feiss line. RESULTS: In bilateral measurement, it was found that the quadriceps angle decreased with age both in the supine and standing positions (p<0.05). It was observed that sex and presence of pes planus had no effect on the quadriceps angle independent from measurement positions (p>0.05). A low negative correlation was found between body mass index and the quadriceps angle in both measurement positions (p<0.05). CONCLUSION: It was found that positional changes and weight bearing on limbs did not cause any change in knee position in healthy children. We consider that the decrease in quadriceps angle in this age group is due to growth rate asymmetry between the femur shaft and pelvic diameter.

3.
J Stroke Cerebrovasc Dis ; 27(8): 2141-2146, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29650380

ABSTRACT

GOAL: The aim of this study was to assess temporomandibular joint dysfunction in patients with stroke. MATERIALS AND METHODS: Total of 100 participants, 50 healthy and 50 who had stroke, were recruited into this study. Digital caliper and algometer were used to assess temporomandibular joint range of motion and masticatory muscle pressure pain threshold. Labial commissure angle measurement was used for the assessment of facial paralysis severity. Fonseca questionnaire was used for temporomandibular joint dysfunction assessment and categorization. In addition, dominant mastication shift was measured by the question that asks the pre and poststroke dominant mastication side. FINDINGS: In intergroup comparison, significant decrease was found in all temporomandibular range of motion parameters in favor of stroke group (P < .05). Despite the fact that no significant difference was found between groups for the pain threshold in masticatory muscles except for middle part of the left temporalis muscle, values were higher in healthy group (P > .05). As a result of intergroup examination of labial commissure angle degree, Fonseca questionnaire score, it was found that labial commissure angle and Fonseca questionnaire scores were higher in stroke group (P < .05). Intragroup examination of patients with stroke showed that dominant mastication side shift was seen in patients with stroke (P < .05). CONCLUSION: It was concluded that, temporomandibular joint dysfunction prevalence was higher in stroke group compared with healthy group and use of modalities specific to temporomandibular joint dysfunction treatment would be beneficial.


Subject(s)
Stroke/complications , Temporomandibular Joint Dysfunction Syndrome/complications , Temporomandibular Joint Dysfunction Syndrome/diagnosis , Diabetes Complications/epidemiology , Diabetes Complications/physiopathology , Humans , Hypertension/complications , Hypertension/epidemiology , Hypertension/physiopathology , Mastication , Masticatory Muscles/physiopathology , Middle Aged , Pain Threshold , Prevalence , Range of Motion, Articular , Stroke/diagnosis , Stroke/epidemiology , Stroke/physiopathology , Surveys and Questionnaires , Temporomandibular Joint Dysfunction Syndrome/epidemiology , Temporomandibular Joint Dysfunction Syndrome/physiopathology
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