scholarly journals On the Investigation of Effective Factors on Higher Heating Value of Biodiesel: Robust Modeling and Data Assessments

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Shicheng Wang ◽  
Wei Li ◽  
Issam Alruyemi

Higher heating value (HHV) is one of the properties of biomass fuels which is essential in investigating their special characteristics and potentialities. In this paper, various techniques based on Gaussian process regression (GPR) were utilized to assess this value for biomass fuels, including several kernel functions, i.e., exponential, Matern, rational quadratic, and squared exponential. An extensive databank was collected from literature. The findings were compared, and the results indicated that Exponential-based model was more accurate, with the coefficient of regression ( R 2 ) of 0.961 and the mean relative error (% MRE) of 3.11 for total data. Compared to former models presented by previous researchers, the model proposed in this study showed a higher ability to predict output values. With various analyses, it can be concluded that the proposed method has a high rate of efficiency in assessing the HHV of various biomass.

Hand ◽  
2021 ◽  
pp. 155894472110031
Author(s):  
Nicholas H. Lake ◽  
Rafae Khan ◽  
Kyle W. Mombell ◽  
Mary Fergus ◽  
Dominic Gomez-Leonardelli

Background Scaphoid nonunion can occur in up to 55% of displaced scaphoid fractures. Long-term functional outcomes of this injury are lacking. In addition, no study has published rate of return to active military service after this injury. Our goal was to educate providers and patients on expected functional outcomes and return to duty after treatment of scaphoid nonunion. Methods We conducted a retrospective review of patients who underwent scaphoid nonunion repair at our institution from 2008 to 2017. The primary outcome measures were union rates, return to duty rates, and functional outcome scores obtained by telephone call. A total of 144 patients were included and 40 responded to our call for long-term follow-up. Results A total of 72% of patients achieved union after surgery, 18% required revision surgery, and 74% of patients were able to return to full duty after surgery. However, this number progressively decreased at 1, 2, and 5 years after surgery. At an average of 5.9 years after surgery, the mean Quick Disabilities of the Arm, Shoulder, and Hand (qDASH) score was 23.9. The mean qDASH for patients who achieved union (21.9) was significantly lower than those with persistent nonunion (29.2) ( P = .0115). Conclusion Scaphoid nonunion is a difficult problem in the military. We found a high rate of persistent nonunion often requiring revision to partial or full wrist arthrodesis. In addition, our long-term functional outcome scores demonstrate significant disability after this injury, even when union is achieved. This information can help us better counsel our patients and set expectations after treatment of this injury.


Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Brian Liu ◽  
Arismendy Nunez-Garcia ◽  
Cao Tran ◽  
Michael Wu

Introduction: Catheter ablation of atrial fibrillation (AF) guided by spatiotemporal dispersion (SD) of electrograms has been proposed as an ablation strategy to treat patients with persistent AF. However, external validation of this technique is lacking. Here we report a single center experience using ablation by SD. Hypothesis: Targeting regions with SD is associated with a high rate of termination and favorable freedom from AF among patients with persistent AF. Methods: Patients with persistent AF who underwent SD from November 2018 to January 2020 were included in this study. All patients underwent pulmonary vein isolation (PVI) in addition to targeting areas of SD. Lesions on areas of electrogram dispersion were anchored to the PVI or to mitral or posterior wall lines where appropriate. EKG, Holter, event monitors or device interrogations were obtained at 3 and 6 months to assess for arrhythmia recurrence. Results: 44 patients met the inclusion criteria and were included in the study. The patients had a mean age of 69±8 years and were 68 % male. The prevalence of comorbidities was as follows: hypertension (89%), diabetes (21%), OSA (37%) and CAD (26%). Average CHADSVASC score was 2.9±1.4, LVEF was 53±11% and left atrium (LA) diameter was 5.2±1 cm. The recurrence rate of AF at 6 months was 14% whereas the recurrence of atrial tachycardia was 20%. Acute AF termination was observed in 73% of the patients. Termination to sinus occurred in 38% of the patients and the remaining terminated to atrial tachycardia which was subsequently ablated to sinus. The mean procedure duration was 240±90 minutes. Univariate analysis showed recurrence was associated with LA diameter (r=.52; p<.001). No recurrences were observed among patients with a LA diameter < 5 cm. Termination rates were higher among patients with LA diameter < 5 cm when compared to LA diameter ≥ 5 cm. However, it did not reach statistical significance (80% vs. 60%; p=.21). Conclusions: The target of electrograms with SD during AF ablation added to PVI was associated with a high termination rate and a good freedom from AF recurrence at 6 months. The ideal candidate for this procedure may be those with LA diameter < 5 cm among persistent AF. The long-term efficacy of this technique merits further studies in larger populations.


2018 ◽  
Vol 08 (01) ◽  
pp. 037-042
Author(s):  
William Aibinder ◽  
Ali Izadpanah ◽  
Bassem Elhassan

Background Management of scapholunate (SL) ligament disruption is a challenging problem. The reduction and association of the scaphoid and lunate (RASL) procedure has been described with varying results. This study assessed the outcomes of the RASL procedure. Purpose The objective of this study was to assess the outcomes of patients undergoing the RASL procedure at our institution in regard to pain relief, range of motion, radiographic and functional outcomes, complications, and reoperations. Materials and Methods Twelve patients with symptomatic chronic SL instability underwent the RASL procedure. The mean age was 35 years. The mean time from injury to surgery was 40 weeks. The mean follow-up was 89 months. Outcomes included visual analog score for pain, wrist range of motion, grip strength, and Mayo Wrist Scores. Preoperative and postoperative radiographs were reviewed. Results Pain scores improved in 10 wrists. Range of motion and grip strength worsened. The average Mayo Wrist Score was 63.3. The mean SL diastasis and angle improved, but seven wrists developed progressive degenerative changes, with two requiring a salvage procedure. Symptomatic progressive screw lucency occurred in eight wrists requiring screw removal. Conclusion The RASL procedure can improve SL widening but has a high rate of early failure and reoperation. Following reoperation, long-term follow-up demonstrates reasonable long-term durability in some cases. Level of Evidence This is a Level IV, therapeutic case study.


2018 ◽  
Vol 204 ◽  
pp. 04011
Author(s):  
Woranuch Jangsawang

A down draft biomass gasifier stove with four steps of cleaning gas system was developed to produce the producer gas for replacing LPG for cooking applications in lunch project for the student in rural school area. This project has been implemented at Bangrakam primary school that located at Pitsanuloke Province, Thailand. The biomass fuels used are Mimosa wood twigs. The gasifier stove was developed based on down draft fixed bed gasifier with the maximum fuel capacity of fourteen kilograms. The performance testing of the biomass gasifier stove showed that the heating value of the producer gas is 4.12 MJ/Nm3 with the thermal efficiency in the percentage of 85.49. The results from this study imply that it has high potential to replace LPG with producer gas.


2021 ◽  
Vol 11 (21) ◽  
pp. 10373
Author(s):  
Zichen Lu ◽  
Jiabin Jiang ◽  
Pin Cao ◽  
Yongying Yang

Due to the imperfect assembly process, the unqualified assembly of a missing gasket or lead seal will affect the product’s performance and possibly cause safety accidents. Machine vision method based on deep learning has been widely used in quality inspection. Semi-supervised learning (SSL) has been applied in training deep learning models to reduce the burden of data annotation. The dataset obtained from the production line tends to be class-imbalanced because the assemblies are qualified in most cases. However, most SSL methods suffer from lower performance in class-imbalanced datasets. Therefore, we propose a new semi-supervised algorithm that achieves high classification accuracy on the class-imbalanced assembly dataset with limited labeled data. Based on the mean teacher algorithm, the proposed algorithm uses certainty to select reliable teacher predictions for student learning dynamically, and loss functions are modified to improve the model’s robustness against class imbalance. Results show that when only 10% of the total data are labeled, and the imbalance rate is 5.3, the proposed method can improve the accuracy from 85.34% to 93.67% compared to supervised learning. When the amount of annotated data accounts for 20%, the accuracy can reach 98.83%.


PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0255533
Author(s):  
Victor Angelo Martins Montalli ◽  
Patrícia Rejane de Freitas ◽  
Milenna de Figueiredo Torres ◽  
Oscar de Figueiredo Torres Junior ◽  
Dienne Hellen Moutinho De Vilhena ◽  
...  

Dental procedures produce a large amount of spatter and aerosols that create concern for the transmission of airborne diseases, such as Covid-19. This study established a methodology with the objective of evaluating new associated strategies to reduce the risk of cross-transmission in a health environment by simulating spread of potentially contaminated dispersion particles (PCDP) in the environment. This crossover study, was conducted in a school clinic environment (4 clinics containing 12 dental chairs each). As a positive control group (without barriers), 12 professionals activated at the same time the turbine of dental drill, for one minute, with a bacterial solution (Lactobacillus casei Shirota, 1.5x108 CFU/mL), which had been added in the cooling reservoir of the dental equipment. In the experimental groups, the professionals made use of; a) an individual biosafety barrier in dentistry (IBBD) which consists of a metal support covered by a disposable PVC film barrier; b) a Mobile Unit of Disinfection by Ultraviolet-C, consisting of 8 UV lamps-C of 95W, of 304μW/cm2 of irradiance each, connected for 15 minutes (UV-C) and; c) the association between the two methods (IBBD + UV-C). In each clinic, 56 Petri dishes containing MRS agar were positioned on the lamps, benches and on the floor. In addition, plates were placed prior to each test (negative control group) and plates were also placed in the corridor that connects the four clinics. In the groups without barrier and IBBD + UV-C the passive air microorganisms in Petri dishes was also evaluated at times of 30, 60, 90 and 120 minutes after the end of the dental’s drill activation. The mean (standard deviation) of CFU of L. casei Shirota for the positive control group was 3905 (1521), while in the experimental groups the mean using the IBBD was 940 (466) CFU, establishing a reduction on average, of 75% (p<0.0001). For the UV-C group, the mean was 260 (309) CFU and the association of the use of IBBD + UV-C promoted an overall average count of 152 (257) CFU, establishing a reduction on average of 93% and 96%, respectively (p<0.0001). Considering these results and the study model used, the individual biosafety barrier associated with UV-C technology showed to be efficient strategies to reduce the dispersion of bioaerosols generated in an environment with high rate of PCDP generation and may be an alternative for the improvement of biosafety in different healthy environment.


2019 ◽  
Vol 4 (2) ◽  
pp. 83
Author(s):  
Isam Bsisu ◽  
Alaa Aldalaeen ◽  
Rawan Elrajabi ◽  
Ala AlZaatreh ◽  
Rama Jadallah ◽  
...  

<p><strong><em>Background:</em></strong><em> Preterm premature rupture of membranes (PPROM) is responsible for one?third of all preterm births worldwide. This aim of this study was to investigate the outcome of neonates born after prolonged PPROM with gestational age below 34 weeks. </em></p><p><strong><em>Materials and methods:</em></strong><em> This retrospective study included 65 patients who were born to mothers with Prolonged PPROM &lt;34 weeks gestation between January 2011 and December 2015 and admitted to the neonatal intensive care unit (NICU) at Jordan University Hospital. </em></p><p><strong><em>Results: </em></strong><em>The mean gestational age of included patients was (31.9 ± 2.5 weeks), mean birth weight was (1840 ± 583 g) and 43 (66.2%) were males. The mortality rate in those infants was 12.3 %. Gestational age, birth weight, and Apgar score were significantly lower among mortality cases compared to surviving cases (P &lt; 0.05). </em></p><p><strong><em>Conclusion:</em></strong><em> Prolonged PPROM before the 34<sup>th</sup> gestational week is associated with high rate of morbidity and mortality, for which early identification of risk factors for developing PPROM can help in reducing the risk for preterm labors and subsequent burden on healthcare system.</em></p>


2020 ◽  
Vol 24 (3) ◽  
pp. 112-118
Author(s):  
Dace Âriņa ◽  
Rūta Bendere ◽  
Gintaras Denafas ◽  
Jānis Kalnačs ◽  
Mait Kriipsalu

AbstractThe authors determined the morphological composition of refuse derived fuel (RDF) produced in Latvia and Lithuania by manually sorting. The parameters of RDF (moisture, net calorific value, ash content, carbon, nitrogen, hydrogen, sulphur, chlorine, metals) was determined using the EN standards. Comparing obtained results with data from literature, authors have found that the content of plastic is higher but paper and cardboard is lower than typical values. Results also show that the mean parameters for RDF can be classified with the class codes: Net heating value (3); chlorine (3); mercury (1), and responds to limits stated for 3rd class of solid recovered fuel. It is recommended to separate biological waste at source to lower moisture and ash content and increase heating value for potential fuel production from waste.


2018 ◽  
Vol 25 (5) ◽  
pp. 592-598 ◽  
Author(s):  
Yoshimitsu Soga ◽  
Miho Nakamura ◽  
Kaoru Hirose ◽  
Nobuhiro Ito ◽  
Yusuke Tomoi ◽  
...  

Purpose: To evaluate the use of the TruePath crossing device as the primary recanalization tool for infrainguinal chronic total occlusions (CTO). Methods: A retrospective analysis was conducted of 50 patients (mean age 75 years; 26 men) with 55 infrainguinal CTOs treated with the TruePath between March 2017 and September 2017 at a single center. The mean occlusion length was 138±55 mm, and femoropopliteal lesions accounted for 65% of the 55 lesions. The primary outcome measure was CTO crossing using the TruePath alone; secondary outcomes were assisted success (>50% lumen gain using the TruePath), device-related complications, and intraluminal crossing evaluated by intravascular ultrasound (IVUS). Results: Complete success was achieved in 33 (60%) of 55 lesions having a mean occlusion length of 145±72 mm. Among these, the true lumen crossing rate was 97% according to IVUS evaluation. Assisted success was achieved in 15 (68%) of the 22 failures. Complete/assisted success, in which the TruePath was thought to have contributed to CTO crossing, was attained in 48 (87%) of the 55 lesions. Three (5.5%) complications were observed: a perforation, an access-site hematoma, and acute occlusion; only the perforation was device related (1.8%). Multivariate analysis showed PACCS grade 4 (odds ratio 4.5, 95% confidence interval 1.33 to 15.5, p=0.02) was an independent predictor of TruePath failure. Conclusion: Primary use of the TruePath crossing device for infrainguinal CTOs demonstrated a satisfactory complete success rate and a high rate of IVUS-documented intraluminal crossing with few device-related complications. Severe calcification is an independent predictor of TruePath failure.


2021 ◽  
pp. 126960
Author(s):  
Yue Pan ◽  
Xiankui Zeng ◽  
Hongxia Xu ◽  
Yuanyuan Sun ◽  
Dong Wang ◽  
...  

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