Evaluation of the Uncertainty of Selected Parameters that Characterise Diesel Engine Work

2015 ◽  
Vol 712 ◽  
pp. 69-74
Author(s):  
Andrzej Bąkowski ◽  
Leszek Radziszewski
Keyword(s):  
Chamber Pressure ◽  
Statistical Computing ◽  
Compression Ignition ◽  
Compression Ignition Engine ◽  
Mean Values ◽  
The Mean ◽  
The Impact ◽  
The Given ◽  
Free Open Source ◽  
Operating Cycles

The evaluation included the values and uncertainty of the mean indicated pressure in subsequent operating cycles of a diesel-fuelled compression ignition engine. Analysis of combustion chamber pressure deviations from the mean values helped identify disturbance that affected the given signal. The impact of this disturbance was checked for the mean indicated pressure uncertainty and the coefficient of variation (X(pIND)). R, a free, open-source environment and commercially available Matlab software were used for statistical computing.

scholarly journals Biases in CloudSat Falling Snow Estimates Resulting from Daylight-Only Operations

2021 ◽  
Vol 13 (11) ◽  
pp. 2041
Author(s):  
Lisa Milani ◽  
Norman B. Wood
Keyword(s):  
Water Cycle ◽  
Mean Values ◽  
The Mean ◽  
Satellite Missions ◽  
The Impact ◽  
Global Mean

Falling snow is a key component of the Earth’s water cycle, and space-based observations provide the best current capability to evaluate it globally. The Cloud Profiling Radar (CPR) on board CloudSat is sensitive to snowfall, and other satellite missions and climatological models have used snowfall properties measured by it for evaluating and comparing against their snowfall products. Since a battery anomaly in 2011, the CPR has operated in a Daylight-Only Operations (DO-Op) mode, in which it makes measurements primarily during only the daylit portion of its orbit. This work provides estimates of biases inherent in global snowfall amounts derived from CPR measurements due to this shift to DO-Op mode. We use CloudSat’s snowfall measurements during its Full Operations (Full-Op) period prior to the battery anomaly to evaluate the impact of the DO-Op mode sampling. For multi-year global mean values, the snowfall fraction during DO-Op changes by −10.16% and the mean snowfall rate changes by −8.21% compared with Full-Op. These changes are driven by the changes in sampling in DO-Op and are very little influenced by changes in meteorology between the Full-Op and DO-Op periods. The results highlight the need to sample consistently with the CloudSat observations or to adjust snowfall estimates derived from CloudSat when using DO-Op data to evaluate other precipitation products.

​Impact of Extreme Hot Environmental Temperature Period on Marker Enzymes of Carbohydrate Metabolism in Non-descript Sheep from Arid Tracts of Rajasthan

2021 ◽  
Author(s):  
Anandita Srivastava ◽  
Nalini Kataria
Keyword(s):  
Carbohydrate Metabolism ◽  
Environmental Temperature ◽  
Age Groups ◽  
Extreme Temperature ◽  
Mean Value ◽  
Marker Enzymes ◽  
Mean Values ◽  
The Mean ◽  
The Impact ◽  
Enzymes Of Carbohydrate Metabolism

Background: The present investigation was envisaged to find out the impact of extreme hot environmental temperature period (ETP) on marker enzymes of carbohydrate metabolism in male and female non-descript sheep of various age groups i.e. 4 to 13 months from arid tracts of Rajasthan. Glucose-6-phosphate dehydrogenase (G-6-PDH) and malate dehydrogenase (MDH) marker enzymes of carbohydrate metabolism were considered for study. Methods: During the period October 2016-June 2017 blood samples were collected to harvest sera for spectrophotometric method from 240 healthy animals selected from private slaughter house during moderate and extreme hot environmental temperature periods (ETPs). The mean values of markers attained during moderate ETP were reckoned as the control. It was 10.00 ± 0.10 UL-1 and 42.00±1.00 respectively. Conclusion: The mean value of MDH was significantly (p≤0.05) higher while G-6-PDH significantly (p≤0.05) lowers during extreme hot temperature in comparison to moderate period. Therefore, it could be concluded that variations in enzyme markers were associated with changes in environmental temperatures. Probably ETP were able to produce a profound effect on carbohydrate metabolism in sheep. Therfore it can be suggested that during the period of extreme temperature balanced ration must be provided to the animal along with proper management to decrease the severity of temperature impact.

scholarly journals Records of performance and sanitary status from a dairy cattle herd in southern Brazil

2011 ◽  
Vol 31 (1) ◽  
pp. 01-09 ◽  
Author(s):  
Cláudio E. F. Cruz ◽  
Djeison L. Raymundo ◽  
Cristine Cerva ◽  
Saulo P. Pavarini ◽  
André G. C. Dalto ◽  
...  
Keyword(s):  
Dairy Cattle ◽  
Reproductive Performance ◽  
Cattle Herd ◽  
Lactation Period ◽  
Mean Values ◽  
Cattle Diseases ◽  
Dairy Cattle Herd ◽  
The Mean ◽  
The Impact ◽  
Voluntary Waiting Period

Over the last decades, the emphasis on the health of dairy cows has changed from an individual to a herd level. In this scenario, the role played by the recording system and its interpretation by veterinarians has gained primordial importance. The records of productive and reproductive performance and of sanitary status from a southern Brazilian dairy cattle herd have been presented and discussed. The period of study was 2000-2009. Mean values per lactation period were 349D 8436M 290F 275P 201SCS (D: days in lactation, M: kg of milk yield, F: kg of fat, P: kg of protein and SCS: somatic cell score in 1000 cells/ml of milk). Major indexes of reproductive efficiency included age at first calving (31 months), services per conception (2.1), intercalving interval (428 days), calving to conception interval (146 days), mean annual rates of parturitions (76.2%), fetal losses (9.8-19.0%), and stillbirths (3.6%), apart of voluntary waiting period (94 days). Main information on sanitary status of the herd was associated with the mean prevalence of common disorders of dairy cattle such as anaplasmosis (29.8%), mastitis (27.8%), digital diseases (26.3%), ovarian cysts (21.3%), placental retention (19.7%), postpartum uterine infections (10.6%), and calf diarrhea (23.7%) and pneumonia (16.8%), among others. In addition, culling reasons (low reproductive performance [56.3%] and udder/mastitis problems [33.6%]), causes of cattle deaths (anaplasmosis [16.4%] and leukosis [11.4]), and the impact of cattle diseases such as tuberculosis, leukosis, and neosporosis on the herd have also been presented and succinctly discussed. Numbers between brackets represent rates accumulated in the 10-year period.

Predicted Qualitative Effects of Alternate Liquid Fuels on Heavy-Duty Compression-Ignition Engines

2009 ◽  
Author(s):  
Gong Chen
Keyword(s):  
Fuel Injection ◽  
Cetane Number ◽  
Fuel Properties ◽  
Liquid Fuels ◽  
Compression Ignition ◽  
Heavy Duty ◽  
Compression Ignition Engine ◽  
End Effects ◽  
Compression Ignition Engines ◽  
The Impact

It is always desirable for a heavy-duty compression-ignition engine, such as a diesel engine, to possess a capability of using alternate liquid fuels without significant hardware modification to the engine baseline. Because fuel properties vary between various types of liquid fuels, it is important to understand the impact and effects of the fuel properties on engine operating and output parameters. This paper intends and attempts to achieve that understanding and to predict the qualitative effects by studying analytically and qualitatively how a heavy-duty compression-ignition engine would respond to the variation of fuel properties. The fuel properties considered in this paper mainly include the fuel density, compressibility, heating value, viscosity, cetane number, and distillation temperature range. The qualitative direct and end effects of the fuel properties on engine bulk fuel injection, in-cylinder combustion, and outputs are analyzed and predicted. Understanding these effects can be useful in analyzing and designing a compression-ignition engine for using alternate liquid fuels.

scholarly journals Ultrasound-based examination of the medial ligament complex shows gender- and age-related differences in laxity

2020 ◽  
Author(s):  
Patricia M. Lutz ◽  
Matthias J. Feucht ◽  
Judith Wechselberger ◽  
Michael Rasper ◽  
Wolf Petersen ◽  
...  
Keyword(s):  
Knee Joint ◽  
Knee Flexion ◽  
Joint Space ◽  
Medial Knee ◽  
Mean Values ◽  
Age Related ◽  
Gender And Age ◽  
Joint Width ◽  
The Mean ◽  
The Impact

Abstract Purpose Ultrasound (US) examination of the medial joint space of the knee has played a subordinate diagnostic role up till now. The purpose of the present study was to describe mean values of medial joint width and to investigate the impact of gender, age, and body mass index (BMI) on medial joint laxity in healthy knees using modern, dynamic US in a standardized fashion in unloaded and standardized loaded conditions. Methods A total of 65 subjects with 79 healthy knees were enrolled in this study. All volunteers underwent clinical examination of the knee. The medial knee joint width was determined using US in a supine position at 0° and 30° of knee flexion in unloaded and standardized loaded (= 15 Dekanewton, daN) conditions using a specific device. Mean values were described and correlations between medial knee joint width and gender, age, and BMI were assessed. Results Thirty-two females and 33 males were enrolled in this study. The mean medial joint width in 0° unloaded was 5.7 ± 1.2 mm and 7.4 ± 1.4 mm loaded. In 30° of knee flexion, the mean medial joint width was 6.1 ± 1.1 mm unloaded and 7.8 ± 1.2 mm loaded. The average change between unloaded and loaded conditions in 0° was 1.7 ± 1.0 mm and in 30° 1.7 ± 0.9 mm. A significant difference between genders was evident for medial joint width in 0° and 30° of flexion in unloaded and loaded conditions (p < 0.05). With rising age, a significant increased change of medial joint space width between unloaded and loaded conditions could be demonstrated in 0° (p = 0.032). No significant correlation between BMI and medial joint width in US could be found. Conclusion Mean values of medial joint width in unloaded and standardized loaded conditions using a fixation device could be demonstrated. Based on the results of this study, medial knee joint width in US is gender- and age-related in healthy knees. These present data may be useful for evaluating patients with acute or chronic pathologies to the medial side of the knee. Level of evidence III.

Discordant GH and IGF-1 Results in Treated Acromegaly: Impact of GH Cutoffs and Mean Values Assessment

2020 ◽  
Author(s):  
Claudia Campana ◽  
Francesco Cocchiara ◽  
Giuliana Corica ◽  
Federica Nista ◽  
Marica Arvigo ◽  
...  
Keyword(s):  
Characteristic Curve ◽  
Area Under The Curve ◽  
Receiver Operator Characteristic Curve ◽  
Mean Values ◽  
Pituitary Diseases ◽  
Discordance Rate ◽  
Values Assessment ◽  
The Mean ◽  
The Impact

Abstract Context Discordant growth hormone (GH) and insulin-like growth factor-1 (IGF-1) values are frequent in acromegaly. Objective To evaluate the impact of different GH cutoffs on discordance rate. To investigate whether the mean of consecutive GH measurements impacts discordance rate when matched to the last available IGF-1 value. Design Retrospective study. Setting Referral center for pituitary diseases. Patients Ninety acromegaly patients with at least 3 consecutive evaluations for GH and IGF-1 using the same assay in the same laboratory (median follow-up 13 years). Interventions Multimodal treatment of acromegaly. Main Outcome Measures Single fasting GH (GHf) and IGF-1 (IGF-1f). Mean of 3 GH measurements (GHm), collected during consecutive routine patients’ evaluations. Results At last evaluation GHf values were 1.99 ± 2.79 µg/L and age-adjusted IGF-1f was 0.86 ± 0.44 × upper limit of normality (mean ± SD). The discordance rate using GHf was 52.2% (cutoff 1 µg/L) and 35.6% (cutoff 2.5 µg/L) (P = 0.025). “High GH” discordance was more common for GHf &lt;1.0 µg/L, while “high IGF-1” was predominant for GHf &lt;2.5 µg/L (P &lt; 0.0001). Using GHm mitigated the impact of GH cutoffs on discordance (GHm &lt;1.0 µg/L: 43.3%; GHm &lt;2.5 µg/L: 38.9%; P = 0.265). At receiver-operator characteristic curve (ROC) analysis, both GHf and GHm were poor predictors of IGF-1f normalization (area under the curve [AUC] = 0.611 and AUC = 0.645, respectively). The prevalence of disease-related comorbidities did not significantly differ between controlled, discordant, and active disease patients. Discussion GH/IGF-1 discordance strongly depends on GH cutoffs. The use of GHm lessen the impact of GH cutoffs. Measurement of fasting GH levels (both GHf and GHm) is a poor predictor of IGF-1f normalization in our cohort.

Heat Transfer in Compression-Ignition Engines: First Paper: Heat Transfer in a Quiescent Chamber Diesel Engine

1970 ◽  
Vol 185 (1) ◽  
pp. 963-975 ◽  
Author(s):  
N. D. Whitehouse
Keyword(s):  
Heat Transfer ◽  
Combustion Chamber ◽  
Realistic Model ◽  
Compression Ignition ◽  
Usual Model ◽  
Mean Values ◽  
Transfer Rates ◽  
Compression Ignition Engines ◽  
Instantaneous Values ◽  
The Mean

Instantaneous and mean values of heat transfer at various positions in the combustion chamber were obtained, by means of surface thermocouples, for different loads and speeds and compared with those obtained theoretically from synthesized cycle calculations. The results show that the usual model of homogeneity in the cylinder is inadequate for heat transfer calculations. Peak rates of heat transfer when in the vicinity of a fuel spray were comparatively little dependent upon load or speed. At the periphery of the combustion chamber the mean heat transfer rates were appreciably lower than to the cylinder head and piston and the rapid rise in instantaneous values occurred appreciably later. The results all suggest the need for a more realistic model based upon the geometry and penetration of the fuel sprays.

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