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Cyclopentanone from lignocelluloses is a promising renewable biofuel and can be used as diesel alternative fuel. Cyclopentanone has excellent fuel properties and high intramolecular oxygen content, which has the potential in promoting combustion and reducing emissions. In this study, the effects of blending cyclopentanone with diesel on the combustion and emission of common rail diesel engine were investigated. The novelty of this study is to figure out which blending ratio is the most promising for diesel engine. Cyclopentanone is blended with diesel with 10% and 20% ratio by vol., noted as C10 and C20, respectively. Double injection strategy (pre-injection and main-injection) was adopted in this study. Compared with pure diesel, blending cyclopentanone can prolong the ignition delay, increase the peak heat release rate and increase the peak in-cylinder temperature. The emission tests indicate that blending cyclopentanone can effectively reduce the particle number concentrations (PNC) and particle volume concentrations (PVC) compared to diesel. Further, the number geometric mean diameters (NGMD) of cyclopentanone diesel blend fuels are lower than those of diesel and the reduction increases with cyclopentanone blending ratio. However, a little increase in NOx emission is observed. With the increase of EGR ratio, the NOx emissions of all test fuels decrease obviously, the PNCs and PVCs of diesel and C10 increase. PNCs and PVCs of C20 almost remain unchanged when the EGR ratio is no higher than 8%. Consequently, with 8% EGR ratio, C20 has the best effect in reducing both particle and NOx emissions and it has great potential for application on diesel vehicles.

This research examined the effects of ethanol and aromatic compositions in E10 match-blends on the exhaust regulated, greenhouse gases, and unregulated toxic emissions of five China-6 compliant gasoline direct injection vehicles at room and low ambient temperatures. Emissions of a China-6 compliant gasoline and four E10 match-blends having roughly the same total aromatic concentration but containing different aromatic compositions were measured using Fourier transform infrared spectrometer, gas chromatogram-mass spectrometer, and high-performance liquid chromatogram. The results show that ethanol content decreases the fleet-averaged regulated gas and particulate mass (PM) emissions and increases the particulate number (PN), benzene, and toluene emissions. As the aromatic compositions in E10 match-blends shift from toluene to C8 and C9 aromatics, PM and PN emissions significantly increase. The low temperature leads to higher emission factors than the room temperature, especially the emissions from the fuel with more toluene content. C8 and C9 aromatics are found to have larger impacts on PM emissions but smaller impacts on PN emissions than the C10 and C10+ aromatics. It is noticed that benzene emissions at the low temperature heavily depend on the fuel toluene concentration.

Cyclopentanol is a promising alternative biofuel for automobiles. In this study, an optical engine was employed to investigate the effects of cyclopentanol blending ratios on combustion characteristics. Cyclopentanol was blended with diesel by 10% and 20% volume, denoted as CP10 and CP20, respectively. Comparison tests between blends and diesel (denoted as D100) were performed under three injection pressures (100, 120, and 140 MPa) and four injection timings (−6°, −9°, −12° and −15° crank angle after top dead center (°CA ATDC)). The experimental results indicated that the addition of cyclopentanol prolongs the ignition delay, shortens the combustion duration and improves the indicated thermal efficiency. As the injection pressure increases or the injection timing advances, the peak combustion pressures (PCPs) and peak heat release rates (PHRRs) increase. Compared to D100, the PCPs and PHRRs of cyclopentanol/diesel fuel blends are lower and decrease with the increase of cyclopentanol ratio. Blending cyclopentanol in diesel is effective in reducing soot emission, and the reduction effect weakens as the injection pressure increases or the injection timing advances. CP10 is superior to CP20 according to the comprehensive evaluation of combustion and emission, especially at the injection timing of −12°CA ATDC under the injection pressure of 140 MPa.

This work studies torque oscillation control of a hybrid driveline, and proposes a new cross-domain collaborative (C2) control strategy that comprises a notch filter, a PI filter, and a backlash estimator. The C2 control strategy is centered on a notch filter, which is built on digitalization of the driveline system and analyses of oscillation elements in the frequency domain. To enhance the performance of the notch filter in the time domain, a PI filter is connected in series to the notch filter. Considering that the driveline is a nonlinear time system during backlash travel, a backlash estimator is developed to handle the torque control target. The notch frequency and backlash travel time are identified through simulations, and the control strategy and selected parameters are evaluated in road tests. The results indicate that this control strategy can reduce the peak torsion speed to 71%.

An autonomous calibration method based on particle swarm optimization (PSO) is studied for digital twin modelling of an electrified vehicle. To enhance the model robustness and mitigate the computational cost, a hybrid terminating strategy, which is built on a min-max function of the maximum iterations and minimal error, is implemented. A three-fold cross-validation experiment is designed to determine the setting of the terminating strategy. The proposed method is superior to the conventional PSO-based methods that are terminated by maximum iterations and minimal error. It can obtain a digital twin with at least 10% less error and save 45% computing time.

Biofuels have extensive available resources and have an immense potential as promising alternative fuels for automobile. The application advantages of biofuels are mainly reflected as particulate matter (PM) reduction, carbon neutral, greenhouse gases reduction, waste utilization, energy and economic security, and fuel pluralism. Based on the understanding of molecular structure effects of biofuels on soot formation and particles morphology, the effects of alcohols, ethers, esters and biodiesel on spray and combustion process in constant volume bomb in recent years are retrospectively analyzed in this paper. For the mixture, macromolecular ester fuels and polyoxymethylene dimethyl ether (PODE) are conducive to the improvement of liquid spray, while biodiesel, small molecules, dimethyl ether (DME) and alcohols are reversed. Alcohols are advantageous to the extension of mixing time and the increasing of vapor-phase mixture. Through the influence integrated assessment, alcohols show the best performance on the spray, atomization and combustion, while biodiesels show the worst. But in terms of combustion, PODE is the best choice without considering spray and atomization. For binary alternative-diesel fuel blends, methanol or butanol is the best additive based on synthetically considerations on spray, atomization and combustion. To meet the requirements of the fuel application of diesel engine, ternary fuel or even quaternary fuel have been proposed and explored. This review can help to form a systematic understanding on fuel recombining and obtain the guide of clean and efficient fuel formulation for diesel engine.

To investigate the clinical characteristics of infantile subglottic hemangioma (SGH), and to observe the safety and efficacy of propranolol in the treatment of SGH.The data of 21 children diagnosed with SGH and treated with propranolol in our hospital from March 2013 to January 2021 were retrospectively analyzed and followed up.Among the 21 cases, there were 7 males and 14 females. SGH was found 11 left-sided, 9 right-sided and 1 bilateral-sided. The clinical manifestations included stridor (13/21), respiratory distress (6/21), barking cough (5/21), feeding difficulty (4/21), three concave sign (4/21), cyanosis (2/21) and hoarseness (1/21). 8 patients had multiple cutaneous hemangiomas. The age of presentation ranged from 1 to 8 months, with a median of 1.1 months. 18 cases (85.7 %) had a history of misdiagnosis, 14 bronchitis/pneumonia, 5 laryngomalacia, 2 laryngeal obstruction and 1 asthma. The median ages at diagnosis were 3 months, with a range of 1.2-28 months. The treatment duration ranged from 6 to 25.6 months, with an average of (14.3 ± 4.9) months. Age at termination of treatment ranged from 9 to 38 months, with a median of 18.6 months, and only 2 cases were beyond 2 years old at that time. No adverse side effects from propranolol therapy occurred and all 21 cases were cured.We advocate a strong index of suspicion for SGH presenting with respiratory symptoms under 2 years old who has poor effect or repeated condition after routine treatment. Laryngoscopy combined with contrast-enhanced CT can confirm the diagnosis of SGH. Oral propranolol is safe and effective, and that early diagnosis and intervention of propranolol without further delay are crucial to the successful management. We advocate continue propranolol treatment beyond 18 months of age, furthermore, 2 years old may be the best time for therapy termination.

Achieving low-smoke and low-NOx premixed compression ignition (PCI) combustion at a wide engine operating load range has been a challenge; especially in multi-cylinder engines running at higher loads for which less data is available in the literature. More specifically, it is of interest to characterise particle emissions under these conditions and identify their possible reduction benefit in different size classes compared to conventional diesel combustion. Mixing diesel with gasoline (Dieseline) as an incentive to reduce fuel reactivity (cetane-number) and consequently improve premixing is believed to be useful for PCI. In this study, the feasibility and benefits of using low cetane-number (

This study investigated polycyclic aromatic hydrocarbons (PAHs) and soot formation characteristics in laminar jet flames fuelled by primary reference fuels (PRFs) at elevated pressures. Qualitative PAHs and quantitative soot profiles were acquired by using laser-induced fluorescence and laser-induced incandescence, respectively. The backpressure of flames ranged from 1 bar to 5 bar. Proper flames with the volume fraction of iso-octane in PRFs varying between 0% and 100% and flame equivalent ratio varying between 3.0 and 11.4 were stabilised in a pressurised chamber. The effects of backpressure, equivalent ratio and iso-octane ratio on PAHs and soot formation were evaluated. PAHs and soot formation can be promoted by increasing iso-octane ratio, equivalent ratio and backpressure. The data suggest that PAHs with large molecular size are more sensitive to the increase of backpressure compared with those with small molecular size. Backpressure played a positive role in the growth of PAHs size. The averaged soot volume fraction showed an approximate power-law relation with pressure. The measured averaged soot volume fraction was proportional to pn. Pressure exponent n was 1.34–2.17, 1.41–2.12 and 1.56–2.20 at equivalent ratios of 6.2, 8.5 and 11.4, respectively.

In this research, n-hexane flashing jets discharged from two-hole GDI injectors were studied numerically with different superheat levels and inter-hole angles. The mutual interaction between under-expanded flashing jets was discussed in terms of its effect and mechanism. It was found that under certain conditions, the jets deflected towards each other and merged into one jet which moved along the central axis, indicating the occurrence of spray collapse. The spray collapse is ascribed to the pressure drop in the central area between the two jets, which is an effect of the low-pressure cores within individual jets. The pressure drop in the central area is mainly determined by two effects, i.e. the intensity and volume of the low-pressure cores in individual jets, and the formation of the secondary cell which protects the central area from being affected by the ambience. In the transitional stage from non-collapse to fully-collapse, the pressure drop was enhanced with the rise of superheat level or the decrease of inter-hole angle, and the extent of spray collapse increased. Besides, unique shock structures similar to those of under-expanded gaseous twin-jets were formed at high superheat levels, which consist of two primary cells and a secondary cell.

Partially-premixed compression-ignition (PPCI) is an advanced combustion mode that simultaneously reduces particulate and NOx emissions. Fuels with properties intermediate to that of gasoline and diesel are preferred for PPCI. This paper is a follow-on to a recent work published in Fuel from the authors’ research group on the topic of PPCI combustion with ULG75 (75 vol% gasoline/25 vol% diesel). That paper reported the opportunity of using ULG75 and hot external exhaust-gas-recirculation (EGR) for solving the low-load combustion-stability issue caused by the low reactivity of ULG75. That paper also concluded that ‘It was not possible to obtain stable ULG75 PPCI combustion without using low fuel injection pressure’. Additionally, from the point of ULG75’s volatility and viscosity, it does not require as high injection pressure as diesel. This paper assesses the spray characteristics (spray morphology, penetration length, cone angle and droplet size) of ULG75 at low injection pressures (Pinj = 35/75 MPa). In this work, high-speed macroscopic imaging (0.25 million fps) was carried out at backpressure (BP) of 0.1/4.0 MPa, and ambient temperature (Ta) of 25/125 °C. In addition, ultra-high speed microscopic imaging (1 million fps) was carried out at BP = 4 MPa and Ta = 25 °C. The same tests were conducted for diesel, and the results were used for comparisons. Under preheated ambient condition (Ta = 125 °C), ULG75 showed a noticeable improvement in the spray quality as compared to the non-evaporative condition (Ta = 25 °C), indicated by a shorter spray penetration length, larger spray cone angle and spray area. However, no such changes were observed for diesel spray upon increasing Ta from 25 °C to 125 °C. Both Pinj and BP strongly affected the spray penetration length evolution. However, they showed limited impacts on spray cone angle and spray area. In addition to the experimental study, empirical estimations were conducted to predict the spray penetration length, air entrainment and spray droplet size. The calculations predicted smaller SMD for ULG75 than diesel at all conditions and also indicated ambient temperature as a key factor affecting the spray quality, especially at low injection pressures.

In this paper, n-hexane flashing jets discharged from a single-hole gasoline direct injector (GDI) were studied numerically with the adoption of diffuse Eulerian framework and the homogeneous relaxation model (HRM). The fuel temperature ranged from 30 to 130 °C, and the ambient pressure varied from 20 to 101 kPa. The results showed that considerable vaporization started at the counter bore and a liquid core existed near the nozzle exit. Due to drastic vaporization, the pressure within the liquid core increased so the two-phase flow became under-expanded. Violent expansion then occurred and a low-pressure region was formed, which is believed as the origin of the spray collapse under flashing conditions for multi-hole GDI injectors. At high superheat levels, shock wave structures similar to those in highly under-expanded gaseous jets were identified. However, the transonic position located at some distances from the nozzle rather than at the throttle. Besides, vapor fraction played the dominant role in the onset of expansion, while the expansion was ended by the pressure difference between the two sides of the Mach disk.

CrxNiyTi0.05La0.01 (x: y = 1:1, 2:1, 1:2) laser cladded -plasma nitrided composite modified layers were prepared on the surface of N80 steel. The effect of Cr and Ni content on the microstructure, wear resistance and corrosion resistance of the composite modified layer was investigated. The experimental results showed that Cr1Ni1Ti0.05La0.01 and Cr1Ni2Ti0.05La0.01 laser cladded layers are mainly composed of columnar crystals with FCC structure perpendicular to the surface, and Cr2Ni1Ti0.05La0.01 laser cladded layer is composed of equiaxed BCC and FCC crystals. The nitrided layers of the three samples are mainly composed of CrN phase, and the nitrided layer of Cr2Ni1Ti0.05La0.01-cladded sample has the highest content of CrN and the best homogeneity and compactness, but the thickness of its nitrided layer is the smallest and the speed of nitriding is the slowest. Compared with N80 substrate, the hardness of the three cladded layers is improved, which enhances the strength support of the nitrided layer and improves the hardness gradient of cross-section. Among them, the strengthening effect of the Cr2Ni1Ti0.05La0.01-cladded layer is the best. The wear resistance and corrosion resistance of the three composite modified layers are improved compared with the conventional nitrided layer on N80 steel, and the nitrided layer of Cr2Ni1Ti0.05La0.01-cladded sample is the best, and its friction coefficient and wear loss are only about 30% and 35% of the nitrided layer on N80, its corrosion current densities in 3.5% NaCl solution and in 0.5 mol/L H2SO4 solution are reduced about 6 times and 3 orders of magnitude, respectively.

In this paper, the valence electron structure and the bond energy of covalent bonds of α-Fe and e-Fe2N, e-Fe3N and γ′-Fe4N were calculated by means of the empirical electron theory (EET). It was put forward that the valence electron structure parameter related to hardness is the covalent electron density, the valence electron structure parameters related to plasticity are the lattice electron density and the symmetry factor of the atomic bonding strength, the valence electron structure parameters related to corrosion resistance are the atomic total bonding energy and lattice electron density, and the valence electron structure parameter related to stability is the average atomic total bonding energy. The hardening and corrosion resistance mechanism of ion-based nitriding layer was discussed and the influence of three Fe-N compounds on the hardness, brittleness, corrosion resistance and stability were compared and analyzed from the perspective of electron structure. The calculation results show that the three Fe-N compounds, which have larger covalent electron density and average atomic total bonding energy and smaller lattice electron density than α-Fe, can improve the hardness and corrosion resistance of the iron-based surface. Among the three compounds, e-Fe2N has the greatest hardness, corrosion resistance and stability, and the least brittleness. Therefore, during the nitriding process, efforts shall be made to prompt the formation of e-Fe2N as much as possible.

This paper reports the design optimization for a dual clutch transmission (DCT) of a multi-mode axle-split hybrid electric vehicle (HEV). The purpose of optimization is to minimize the equivalent fuel consumption of automobile power demand. The variables that need to be optimized are gear ratio and Shifting threshold value. The optimization is based on a co-simulation platform, in which, the HEV is modelled in LSM Amesim and the control/optimization algorithms are programmed in MATLAB/ Simulink. In this study, the Hybrid Particle Swarm Optimization (HPSO) algorithm is used to solve the optimization problem, which has better global and local search capability comparing with conventional PSO algorithm. The simulation results show that the optimized transmission parameters can guarantee the power demand and have a good fuel economy.

Flame kernel evolution and shock wave propagation in ethanol/air mixtures with laser ignition in a constant-volume chamber was investigated by means of high-speed Schlieren photography. At initial pressure of 0.1 MPa and temperature of 333 K, ignition was performed using a pulsed laser at the second harmonic wavelength with six different laser energies from 75 to 200 mJ, for the equivalence ratios ranging from 0.8 to 1.4. A cross-shaped plasma spot is captured ∼3.0 µs after the laser triggering, whereas the shape of the flame kernel is initially circular and then transforms to an ellipsoid structure. Following the contraction of the plasma, the flame kernel growth rate is initially very different in the four directions and then approaches a steady flame speed. The contraction of the plasma zone is accompanied by a rapid shock wave propagation where, the wave propagation speed is found to be negligibly influenced by the variations in either laser energy or mixture equivalence ratio. Under the test conditions in this study for ethanol/air mixtures, the initial shock wave speed is ∼480 m/s which decays to ∼380 m/s after 20 µs. The shock wave front propagates with a time dependency of about t0.6 when t

In order to mitigate spray collapse and fully utilize the advantage of flash boiling injection in gasoline direct injection (GDI) engines, it is important to understand the flashing jet behavior and its relationship with spray collapse. In this study, n-hexane sprays discharged from a modified single-hole injector and the original five-hole injector were studied. The tests were carried out in a constant volume vessel with injection temperatures from 30 to 130 °C and ambient pressures (Pamb) from 20 to 101 kPa. By analyzing the relationship between the jet width and different parameters including superheat level, nucleation rate, and chemical potential of phase change (Δμ), strong correlation was found between the jet width and Δμ·Pamb−0.5, indicating the radial expansion of flashing jets was determined by chemical potential of phase change and ambient resistance. Beyond 20d0, the correlation was gradually weakened along the axis, as flash boiling process was finished. Besides, it was found that the extent of single-jet radial expansion was positively related to that of multi-jet spray collapse in the transitional collapse region. Therefore, to mitigate spray collapse, it is necessary to restrict the radial jet expansion, and generating external flashing jets is proposed as a practical approach to realize it.

Cyclopentanone from lignocelluloses is a promising renewable biofuel and can be used as diesel alternative fuel. Cyclopentanone has excellent fuel properties and high intramolecular oxygen content, which has the potential in promoting combustion and reducing emissions. In this study, the effects of blending cyclopentanone on the combustion and emission were investigated on a common rail diesel engine. Cyclopentanone is blended with diesel with 10% and 20% ratio by vol., noted as C10 and C20, respectively. Compared with pure diesel, blending cyclopentanone can prolong the ignition delay, increase the peak heat release ratio and increase the peak in-cylinder temperature. The emission tests indicate that blending cyclopentanone can effectively reduce the particle number concentrations (PNC) and particle volume concentrations (PVC) compared to diesel. Further, the number geometric mean diameters (NGMD) of cyclopentanone diesel blend fuels are lower than those of diesel and the reduction increases with cyclopentanone blending ratio. However, a little increase in NOx emission is observed. With the increase of EGR ratio, the NOx emissions of all test fuels decrease obviously, the PNCs and PVCs of diesel and C10 increase. PNCs and PVCs of C20 almost remain unchanged when the EGR ratio is no higher than 8%. Consequently, with 8% EGR ratio, C20 has the best effect in reducing both particle and NOx emissions and it has great potential for application on diesel vehicles.

Background: Few studies have examined the association between treatment given time and clinical outcomes, which is indeed of great importance to clinical management of coronavirus disease 2019 (COVID-19). We performed this study to explore whether early treatment brings favorable clinical outcomes. Methods: In this retrospective multicenter study, we included patients aged 18 to 87 years with confirmed COVID-19 on admission from 54 hospitals in nine provinces of China from 21 January to 10 March, 2020. Final date of follow-up was March 17, 2020. All patients were treated by Lung cleansing & detoxifying decoction combined with western medicine. Patients were divided into four groups according to the interval from the first date of onset of symptoms to the date of starting a treatment, i.e., ≤1 week group (≤7 days), 1-2 weeks group (>7 days and ≤14 days), 2-3 weeks group (>14 days and ≤21 days) and >3 weeks group (>21 days). Multivariable Cox proportional hazard ratio (HR) models were used to estimate unadjusted and adjusted HRs and 95% confidence intervals (CIs) for the association between the treatment given time and clinical outcomes (time to recovery, days of viral shedding, duration of hospital stay, course of disease, fever and CT images). Findings: Of the 782 patients (median age was 46 years old, and 405 (52%) were male), there were 321 (41%) patients in ≤1 week group, 221 (28%) in 1-2 weeks group, 123 (16%) in 2-3 weeks group and 117 (15%) in >3 weeks group. Compared to patients in later treatment group (greater than 3 weeks), patients in earlier treatment groups of less than 1 week, 1 to 2 weeks, or 2 to 3 weeks had higher likelihood of recovery, with adjusted HR (95% CI) of 3.81 (2.65-5.48), 2.63 (1.86-3.73) and 1.92 (1.34-2.75), respectively. The median days of viral shedding was 13 days and 12 days in 2-3 weeks group and 3 weeks group (P=0.0137). The median course of disease decreased from 34 days to 24 days, 21 days and 18 days when treatment was given every one week in advance compared to that was given later than 3 weeks from the onset of symptoms (P

Background: Novel coronavirus pneumonia (NCP) is often changing rapidly and fatal. Early detection and early triage of coronavirus disease 2019 (Covid-19) is the key to success management of the disease. An easily obtainable yet accurate variable for both diagnosis and prognosis is urgently needed. We aim to report predictive Value of the Neutrophil-to-Lymphocyte Ratio(NLR) for diagnosis and worse clinical course of the COVID-19, which have not been well demonstrated. Methods: Our study consisted of two stages, at the first stage, a retrospective, single-center, cohort study including was conducted in Heilongjiang, on admission, demographic, clinical, and laboratory data were collected and compared between patients with COVID-19 and patients with non COVID-19; we used multivariable logistic regression methods to explore the risk factors associated with COVID-19;A receiver operating characteristic(ROC) analysis was conducted to calculate the area under the curve(AUC) to assess predictive value of NLR for diagnosis of COVID 19. At the second stage, we conducted retrospective, multi-center and large sample study in 43 hospitals from ten provinces of China, COVID-19 patients with laboratory-confirmed divided into three groups including mild cases, ordinary cases and severe cases. Multivariate logistic regression methods were used to identify the risk factors for the deterioration of COVID-19, along with, a receiver operating characteristic (ROC) curve was also drawn to assess impact on the clinical course of the COVID-19. Findings: We recruited a total of 635 patients with COVID-19 and 27 cases with non COVID-19(Viral pneumonia) from 28 January to 25 February. A total of 88 cases were enrolled with a retrospective, single-center, cohort study from Heilongjiang province, of these, COVID-19 cases were 61(69%) and non COVID-19 cases were 27(31%). On admission, fever (69%) was the most common symptoms, cough (56%) and fatigue(53%). An average(SD) of NLR of COVID-19 patients and non- COVID-19 patients were3.48±2.04 and 2.21±1.14, respectively. multivariable regression showed increasing odds of COVID-19 patients associated with NLR(odds ratio 1.752, 95% CI 1.111-2.763, per 1 unit increase; p=0.016). In addition, the area under the curve (AUC) of NLR was 0.707 and cutoff value was 2.22. At the second stage, 635 patients with COVID were enrolled with a retrospective, multi-center, large sample study in the 43 settings from 10 provinces, of these, mild case were 86(14%), ordinary cases [486(76%)],severe cases[63(10%)], common symptoms was at onset of disease were cough[356(56%)], an average of NLR of 635 patients was 4.04±4.68, and elevated NLR with the deterioration of clinical course[mild case(2.73±2.28), ordinary cases(3.58±3.07), severe cases(9.38±10.52), P

Electric vehicles, including plug-in hybrids, are important for achieving net-zero emission and will dominate road transportation in the future. Energy management, which optimizes the onboard energy usage, is a critical functionality of electric vehicles. It is usually developed following the model-based routine, which is conventionally costly and time-consuming and is hard to meet the increasing market competition in the digital era. To reduce the development workload for the energy management controller, this paper studies an innovative transfer learning routine. A new transferable representation control model is proposed by incorporating two promising artificial intelligence technologies, adaptive neural fuzzy inference system and Gaussian process regression, where the former applies k-fold cross valudation to build a neural fuzzy system for real-time implementation of offline optimization result, and the later connects the neural fuzzy system with a ‘deeper’ architecture to transfer the offline optimization knowledge learnt at source domain to new target domains. By introducing a concept of control utility that evaluates vehicle energy efficiency with a penalty on usage of battery energy, experimental evaluations based on the hardware-in-the-loop testing platform are conducted. Competitive real-time control ultility values (as much as 90% of offline benchmarking results) can be achieved by the proposed control method. They are over 27% higher than that achieved by the neural-network-based model.

High tumor mutation burden (TMB-H) could result in an increased number of neoepitopes from somatic mutations expressed by a patient's own tumor cell which can be recognized and targeted by neighboring tumor-infiltrating lymphocytes (TILs). Deeper understanding of spatial heterogeneity and organization of tumor cells and their neighboring immune infiltrates within tumors could provide new insights into tumor progression and treatment response.Here we first developed computational approaches using whole slide images (WSIs) to predict bladder cancer patients' TMB status and TILs across tumor regions, and then investigate spatial heterogeneity and organization of regions harboring TMB-H tumor cells and TILs within tumors, as well as their prognostic utility. Results: In experiments using WSIs from The Cancer Genome Atlas (TCGA) bladder cancer (BLCA), our findings show that computational pathology can reliably predict patient-level TMB status and delineate spatial TMB heterogeneity and co-organization with TILs. TMB-H patients with low spatial heterogeneity enriched with high TILs show improved overall survival.Computational approaches using WSIs have the potential to provide rapid and cost-effective TMB testing and TILs detection. Survival analysis illuminates potential clinical utility of spatial heterogeneity and co-organization of TMB and TILs as a prognostic biomarker in BLCA which warrants further validation in future studies.

The present study is geared towards the investigation of the impact of fuel temperature, ambient pressure, and fuel properties on the spray characteristics of a 6-hole gasoline direct injector. High speed imaging is employed to verify the spray structural variation of various fuels including iso-octane, gasoline, methanol, and ethanol over wide range of operating conditions in an optical vessel. These structural parameters were correlated to the ratio of the ambient to saturation pressure ratio (Pa/Ps) that represents the superheated degree. At a constant pressure of 150 bar the fuel was injected, and the fuel temperature ranged between 25 and 120 °C, whilst the ambient pressure ranged from 0.1 to 1 bar. The results indicated that for all the fuels, the spray width was reduced, and the adjacent plumes collapsed into single bulk as the (Pa/Ps) decreased. Furthermore, at very low (Pa/Ps = 0.065), the spray getting longer, and for iso-octane the fuel spray shrinkage toward the injector centreline and shaped like a Fish with sharpen spray tip. The spray cone angle for ethanol, methanol, and gasoline was reduced when the Pa/Ps ratio was decreased from 1 to 0.16 with the exception that at Pa/Ps = 0.54 for ethanol the cone angle was increased and then decreased with the reduction of Pa/Ps. Then a massive increase in the cone angle was noticed by reducing the Pa/Ps ratio reduced from 0.16 to 0.065. For iso-octane, the behaviour is chaotic and not follow any specific trend with the reduction of Pa/Ps. Furthermore, the appearance of interstitial streams in the gaps between the original spray streams was noticed at Pa/Ps ratio ≤ 0.28. Phase Doppler data showed for the Pa/Ps ratios of 0.85, 0.54, and 0.28, that the interstellar streams consistently had a lower mean droplets velocity and a very narrow head stage compared to that of spray main streams. Moreover, reducing the Pa/Ps ratios of 0.85, 0.28, resulted in a significant reduction in Sauter mean diameter with approximately 49.5%.

Flash boiling injection can significantly promote spray atomization owing to rapid bubble growth and explosion. Nevertheless, the effects of component proportions on spray expansion of multi-component fuels still need more quantitative studies. In this work, a typical non-ideal binary solution (aqueous ethanol solution) was utilized as the injection fluid. The effects of ethanol proportion at varying injection temperatures and ambient pressures were tested in a constant volume vessel. Both increasing injection temperature and decreasing ambient pressure intensified the flashing instant expansion for all tested fluids. Instant expansion of pure water spray can be intensified by adding ethanol but adding ethanol into the aqueous ethanol solution induced an opposite behavior. Such phenomenon was caused by the combined effect of differences in heat capacity and proportions of evaporation components. Hence, superheat level was no longer a suitable index for evaluating the instant expansion between sprays with different component proportions. A new index ΔQ′ was proposed to quantify the expansion extent of binary solutions. A strong correlation was found between expansion extent and ΔQ′∙Pamb−0.75 over a wide condition range, indicating the superheated energy available for the first-vaporizable part of the solution is an important factor controlling the extent of instant expansion for binary solution spray.

Bioenergy attracts more attention owing to the reduction of both air pollution and greenhouse gas emissions in a whole life cycle compared to fossil fuels. As a third-generation biofuel, Microalgae Oil (MAO) can utilise carbon dioxide and light energy at an increased photosynthetic efficiency compared to energy crops for biomass. Due to the wide variety of MAO and their blends with diesel in different ratios, characterization of these biofuels’ engine performance is difficult to be standardized, e.g., in-cylinder pressure. This paper proposes a novel approach of geometric neuro-fuzzy transfer learning (GNFTL) for in-cylinder pressure modelling of a diesel engine fuelled with MAO. Inspired by computational geometry, this approach only utilizes limited experimental data obtained by geometric screening to learn a high-precise transfer model of the in-cylinder pressure with different MAO blending ratios. Followed by the process of MAO extraction and test cell description, the proposed approach of GNFTL is presented which comprises geometric transfer domain segmentation and neuro-fuzzy transfer learning. By a comprehensive study, the results demonstrate that the proposed approach can achieve a competitive prediction accuracy whilst significantly reducing experimental efforts on used biofuel by 47.8% and operation time by 41.5%, compared to the conventional manual design of experiment.

This paper is to investigate the characteristics of trans-critical propane spray compared with the flash boiling spray ejected from a multi-hole injector in a constant volume chamber by using the Schlieren and backlit imaging methods. The fuel temperature ( T f ) is set from 30 °C to 120 °C, injection pressure ( p f ) from 60 bar to 120 bar and ambient pressure ( p a ) from 0.2 bar to 10 bar. The results show that the trans-critical spray has longer vapor penetration and shorter liquid penetration than the flash boiling spray, but those two sprays have similar curve liquid boundaries near the nozzle. Several discernable collapsed shock structures near the nozzle are observed at T f = 120 °C, p f =120 bar, p a = 1 bar, but they disappear when p f drops to 60 bar for the transition path may not enter the two-phase region, and the liquid phase hardly occurs. The Mach disk distance of trans-critical spray in this study is larger than that of the under-expanded ideal gas jet because of the collapse phenomenon. At T f = 120 °C, p f = 120 bar, the liquid length decreases when p a increases from 0.2 bar to 2.5 bar and increases when p a continues to rise.

Understanding spray behaviors is key for the successful employment of high injection pressure systems and biofuels such as 2-methylfuran (MF) and ethanol (ETH) in modern direct-injection gasoline engines. In this present work, the MF spray characteristics in the near-field (up to 1.6 mm) and far-field (up to 48 mm) were experimentally investigated under ultra-high injection pressure of 30, 40 and 50 MPa compared to those of ETH and isooctane (ISO). The effects of injection pressure and fuel properties on the spray morphology, tip penetration and cone angle development have been analyzed. The results showed that MF had a unique spray tip structure with a bubble attached to a mushroom tip at 30 and 40 MPa. The formation of this mushroom tip and bubble was closely related and strongly influenced by the Weber number. Among the three fuels tested, MF presented the lowest spray tip velocity at both near-field and far-field due to its large density. Compared to ETH, MF and ISO always had wider macro cone angles due to their lower viscosity.

In this research, n-hexane jets discharged from a single-hole gasoline direct injector (GDI) were studied in a constant volume vessel. The injection temperature ranged from 20 °C to 100 °C, and the ambient pressure varied from 4 kPa to 101 kPa. The jets were in the external flashing regime over all the superheated conditions with the maximum Rp of 60.23. At the ambient pressures lower than 10 kPa, a liquid core can be observed inside the sprays, surrounded by the mist composed of fine droplets. With the increase in the injection temperature, the length of the liquid core decreased and the mist area became wider. By correlating the nucleation rate with the spray width, it was found that the intensity of bubble blast was positively related to the nucleation rate when the nucleation rates were relatively low. However, as the nucleation rate reached a critical point, the thermal energy for vaporization became the rate-controlling factor. Furthermore, realizing external flashing was proposed as a potential way to mitigate the collapse of multi-jet flashing GDI sprays because it could suppress the severe jet overlap near the nozzle exit, which was believed as one of the necessary conditions for the spray collapse.

The current optical and thermal experimental tests were mainly focused on obtaining a comprehensive understanding of the effects of gasoline direct injector fouling on mass flow rates, spray characteristics, engine emissions and engine performance. A robust injector fouling cycle was employed to produce coked injectors in a multi-cylinder thermal engine. Deposit build-up in the coked injectors and fouling cycle repeatability was first examined by measurements of fuel flow rate. Macroscopic spray characteristics of the clean and the coked injectors were carried out using high-speed imaging and Planar Laser Induced Fluorescence (PLIF) of sprays foot-print. Fuel droplets size and velocity were characterised with a two-dimensional Phase Doppler Particle Analyser (PDPA). It was observed that the deposit build-up inside injector nozzles and on injector tips reduced the plume cone angle while increased plume penetration length, plume separation angles, mean droplet velocity and size for the coked injector. Impact of injector fouling was further investigated by PLIF measurements of in-cylinder charge inhomogeneity and repeatability in mixture preparation. The coked injectors showed higher degree of inhomogeneity and poorer repeatability in mixture preparation. These were in agreement with combustion analysis results where the coked injectors showed lower load and lower combustion stability compared with the clean injector under same operating conditions. Significantly higher unburned hydrocarbon emissions and particulate number concentration were also observed for the coked injectors. This work was carried out to obtain a broad picture of injector cooking effects in GDI engines.