6 research outputs found
Combustion Simulation of a Diesel Engine with Split Injections by Lagrangian Conditional Moment Closure Model
The Lagrangian conditional moment closure (CMC) model is applied to combustion simulation of a diesel engine at different load conditions. Calculation is performed by the free open-source computational fluid dynamics (CFD) package, OpenFOAM (Jasak, 1996). In Lagrangian CMC total injected fuel is divided into a given number of fuel groups with each group assumed to have the same residence time, consequently the same conditional flame structure. The Favre mean quantities are obtained by local conditional flame structures weighted by an assumed probability density function (PDF) through the improved beta-PDF integration method. Calculated pressure traces are compared with measurements in five operating conditions involving a single or multiple injections with different fuel mass ratios, rpms, swirl ratios, and exhaust gas recirculation (EGR) rates. The Lagrangian CMC model showed acceptable agreement with measured pressure traces and apparent heat release rates for all test cases. There was no improvement in the results by flame group interaction, which is considered not relevant in the given engine conditions.11sciescopu
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Analysis of facial sebum distribution using a digital fluorescent imaging system.
Current methods for analysis of sebum excretion have limitations, such as irreproducible results in repeatable measurements due to the point measurement method, user-dependent artifacts due to contact measurement or qualitative evaluation of the image, and long measurement time. A UV-induced fluorescent digital imaging system is developed to acquire facial images so that the distribution of sebum excretion on the face could be analyzed. The imaging system consists of a constant UV-A light source, digital color camera, and head-positioning device. The system for acquisition of a fluorescent facial image and the image analysis method is described. The imaging modality provides uniform light distribution and presents a discernible color fluorescent image. Valuable parameters of sebum excretion are obtained after image analysis. The imaging system, which provides a noncontact method, is proved to be a useful tool to evaluate the amount and pattern of sebum excretion. When compared to conventional "Wood's lamp" and "Sebutape" methods that provide similar parameters for sebum excretion, the described method is simpler and more reliable to evaluate the dynamics of sebum excretion in nearly real-time
Combustion Simulation of a Diesel Engine with Split Injections by Lagrangian Conditional Moment Closure Model
Compensation Strategy of the Numerical Analysis in Frequency Domain on Induction Motor Considering Magnetic Flux Saturation
Surveillance of wild animals carrying infectious agents based on high-throughput screening platform in the Republic of Korea
Abstract Background Infectious diseases transmitted by wild animals are major threats to public health. This study aimed to investigate the potential of rescued wild animals that died of unknown causes as reservoirs of infectious agents. From 2018 to 2019, 121 dead wild animals (55 birds and 66 mammals) were included in this study. All wild animals died during treatment after anthropogenic events. After deaths of animals, necropsies were performed and trachea, lungs, large intestine (including stool), and spleen were collected to determine causes of deaths. A high-throughput screening (HTS) quantitative polymerase chain reaction (qPCR) designed to detect 19 pathogens simultaneously against 48 samples in duplicate was performed using nucleic acids extracted from pooled tissues and peripheral blood samples. If positive, singleplex real-time PCR was performed for individual organs or blood samples. Results The HTS qPCR showed positive results for Campylobacter jejuni (10/121, 8.3%), Campylobacter coli (1/121, 0.8%), Mycoplasma spp. (78/121, 64.5%), and Plasmodium spp. (7/121, 5.7%). Singleplex real-time PCR confirmed that C. jejuni was detected in the large intestine but not in the blood. C. coli was only detected in the large intestine. Mycoplasma spp. were detected in all organs, having the highest proportion in the large intestine and lowest in the blood. Plasmodium spp. was also detected in all organs, with proportions being were similar among organs. Conclusions This study shows that wild animals can become carriers of infectious agents without showing any clinical symptoms
Risk of Hyponatremia after Tramadol/Acetaminophen Single-Pill Combination Therapy: A Real-World Study Based on the OMOPâCDM Database
Abstract Background and Objective Tramadol has been reported to cause hyponatremia but the evidence is conflicting. The risk of hyponatremia resulting from combination oral tramadol/acetaminophen (TA) therapy is thus unknown. This study examined whether, compared with acetaminophen (AA), TA use is associated with an increased risk of hyponatremia. Methods Hospital data compatible with the Observational Medical Outcomes PartnershipâCommon Data Model (OMOPâCDM; version 5.3) for 30,999 patients taking TA or AA from 2011 through 2020 were analyzed. New-onset hyponatremia was defined as a serum sodium level  65 years and 16,654 (53.7%) were male. Hyponatremia within 10 days developed in 1613 (8.4%) of the 19,149 patients in the TA group; the incidence rate was higher than in the AA group (4.2%; 493 out of 11,850 cases). In the propensity-score-matched model, the incidence rate of hyponatremia in the TA group was 6.8 per 1000 person-days (PD), which was 1.57-fold (1.31, 1.89) higher than that in the AA group (4.3 per 1000 PD). In both the crude and propensity-score-matched models, the incidence rate of hyponatremia was significantly higher in the TAâER than TAâIR subgroup. Conclusion In this real-world study, hyponatremia was more frequently observed in the TA than AA group, and in the TAâER than TAâIR subgroup. Therefore, it is imperative to prescribe tramadol cautiously and closely monitor electrolyte levels