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Maritime operations face significant challenges in environmental stewardship, particularly in managing oil discharges from tankers as mandated by the International Convention for the Prevention of Pollution from Ships (MARPOL) Annex I, Regulation 34. Traditional Oil Discharge Monitoring Equipment (ODME) methods rely on manual decision-making, often failing to accurately identify MARPOL-defined no-go zones, estimate operation completion times, and recommend course alterations during decanting operations. This study introduces a novel approach by integrating advanced machine learning techniques—Extreme Gradient Boosting (XGBoost) and Light Gradient Boosting Machine (LightGBM)—to enhance ODME operations. Specifically, these models automate the identification of no-go zones and optimize operational decisions, leading to a 99 % accuracy rate in compliance with MARPOL regulations and an operational time estimation error margin of <1 %. Unlike traditional methods, our approach leverages large datasets and real-time GPS (Global Positioning System) data, significantly reducing human error and enhancing both environmental compliance and operational efficiency. To our knowledge, this is the first study to specifically address the application of machine learning to decanting operations under MARPOL Annex I, marking a significant advancement in maritime environmental management. [Display omitted] • Significant enhancement in environmental compliance and operational efficiency. • Real-time GPS integration ensures MARPOL regulatory adherence. • Advanced ML models (XGBoost, LightGBM) enhance ODME capabilities. • Novel approach eliminates human error in ODME operations using large datasets. • First study to address MARPOL Annex I decanting operations with machine learning. [ABSTRACT FROM AUTHOR]

A series of diesel spray combustion tests was carried out in a constant volume combustion chamber (CVCC) to investigate the effect of multiple injection strategies on cold startability. The experiments were performed under a simulated low temperature cold start condition. In-chamber pressure analysis and high speed flame imaging were conducted to compare the effectiveness of each injection strategy on cold startability. Spray targeting visualization was also performed to examine the wall impingement of injected fuel. The diesel fuel was injected into the CVCC with an injection pressure of 35 MPa. Multiple injection strategies with different amounts of pilot injection quantities were applied to improve the diesel combustion under simulated cold start ambient condition. The flame imaging and in-chamber pressure results showed that the multiple injection strategy provided better cold startability than the single injection condition. According to the pilot injection quantity, the peak of the flame luminosity and in-chamber pressure were gradually increased with larger pilot injection quantity cases. The peak of the variation rate of the in-chamber pressure with a multiple injection strategy was approximately 2 times higher than that of the single injection case. In terms of spray targeting imaging, the results indicated that the fuel impingement and flow to the piston crevice volume were increased with a larger amount of pilot2 injection. Therefore, the increment of the pilot1 injection quantity rather than the pilot2 injection quantity was suggested not only to improve cold startability, but also to reduce unburned hydrocarbon emissions under a cold start condition in a real engine. [ABSTRACT FROM AUTHOR]

The cold start issue has been a problem in diesel engines. Thus, in the present research, the diesel fuel flow and macroscopic spray characteristics over a wide fuel temperature range were investigated to provide valuable insights for solving the cold start problem. An injection system including a common-rail and a fuel supplier was designed to control the fuel temperature from 243 K to 313 K. For the fuel flow characteristics, the results showed that the injection quantity decreased by 50% as the fuel temperature decreased from 313 K to 243 K under the same energizing time. It was also confirmed that the real start of injection timing was retarded as the fuel temperature decreased. The reason is that increased fuel viscosity disturbed the injector needle motion and fuel flow in the nozzle. The spray test was performed under the simulated cold start condition using a constant-volume combustion chamber (CVCC). For the macroscopic spray characteristics, the liquid-phase fuel penetration increased and the spray angle decreased with cold fuel due to attenuated fuel evaporation process and interaction with ambient gas. These results could cause poor air–fuel mixing process under the cold starting. [ABSTRACT FROM AUTHOR]

High amount of unburned hydrocarbon emission and combustion instability are serious problems in diesel engines during cold starting. In order to solve these troubles, the effects of fuel temperature on spray and combustion should be understood. In this study, macroscopic spray and combustion experiments were carried out over a wide range of fuel temperatures from 243 to 313 K. The tests were performed under simulated low temperature cold start condition. In-chamber pressure analysis and high speed imaging were combined in a constant-volume combustion chamber (CVCC). The diesel fuel was injected into the CVCC under simulated engine operating conditions with an injection pressure of 35 MPa. The cold diesel fuel showed a longer liquid penetration length and a narrower spray angle in macroscopic spray imaging. The reasons for the deteriorated spray characteristics were revealed to be the attenuation of the fuel evaporation and ambient air entrainment. In combustion imaging, partial misfires of the diesel spray were detected under cold start condition. On the other hand, all of spray plumes were successfully ignited under hot start condition. The peaks of in-chamber pressure and flame luminosity were decreased with cold fuel because of the poor air–fuel mixture preparation during the ignition delay period. [ABSTRACT FROM AUTHOR]

An experimental study was conducted to investigate the effects of the proportion between high pressure and low pressure exhaust gas recirculation (HP/LP EGR) on engine operation. The study focused on the characteristics of combustion, emissions, and fuel consumption in a 2.2 L passenger car diesel engine. The experiments were performed under three part-load and steady-state operating conditions. The LP EGR portion was swept from 0 to 1, while the mass flow rate of fresh air and boost pressure were fixed. The results showed that the intake manifold temperature decreased gradually as the LP EGR portion increased due to its greater cooling capability by a longer supply line and an intercooler. However, the required cooling power for the intercooler increased because the LP EGR gas, which has a higher temperature than the fresh air, was induced upstream of the compressor. The lowered intake manifold temperature with the increase of the LP EGR portion led to the prolonged ignition delay of pilot injections, which resulted in a slightly higher peak heat release rate in the main combustion. A higher LP EGR portion showed a lower fuel consumption level than the HP EGR only case because the variable geometry turbocharger (VGT) nozzle opened more widely to maintain the boost pressure, which means a lower pumping loss. Nitrogen oxide (NOx) emissions were also decreased as the LP EGR portion increased due to lowered intake charge temperature. Consequently, it was possible to improve the trade-off relationship between NOx emissions and fuel consumption with the increase of the LP EGR portion under steady-state operating conditions. [ABSTRACT FROM AUTHOR]

The wear of orthopaedic prostheses results in the release of a markedly heterogeneous assortment of particulate debris, with respect to both size and shape. Although particle size has been extensively examined, the role of particle shape in adverse inflammatory reactions to debris remains unclear. Using an in vivo murine model of inflammation, we assessed tissue responses to globular and to elongated ultra-high molecular weight polyethylene (UHMWPE) particles with a similar surface area, and investigated whether inflammation and cellular apoptosis varied with particle shape in the debris–tissue interaction. Histological changes of UHMWPE-stimulated pouch membrane were assessed using a computerized image analysis system. Quantitative real time PCR and ELISA were performed to assess mRNA expression and protein level of the cytokines, and TUNEL assays were conducted to quantify apoptotic cells. The data revealed that elongated particles generated more active inflammatory air pouches, stimulated more severe membrane proliferation and the inflammatory cellular infiltration compared to globular particles. Increased levels of IL-1β and TNFα were detected in the lavage and homogenate of pouches stimulated with elongated particles in comparison to pouches with globular particles, and the apoptotic assay indicated more severe apoptotic changes within the inflammatory membrane provoked with elongated particles. Our results suggest that cellular responses to UHMWPE wear debris are dependent on the shape of the particles. [Copyright &y& Elsevier]

Abstract: In order to optimize the metalorganic chemical vapor deposition process for PbZr x Ti1−x O3 (PZT) thin films, the effect of purge gas species was investigated. Two steps of gas input process for stabilizing reaction chamber pressure, the gas flow prior to PbTiO3 (PTO) seed layer deposition and PZT thin film deposition, were varied and their effect on structural and electrical properties were examined with regard to the memory device application. PZT film properties exhibited remarkable dependency on the gas species before PTO seed deposition, and insignificant dependency on the gas species before PZT film deposition. With the optimized pre-deposition gas flow, PZT thin film showed excellent properties such as high (111)-orientation (92.2%), high remnant polarization value of 71μC/cm2 at 3V. Retention property also showed a heavy dependency on the pre-deposition gas flow that 91.1% of initial charge could be maintained after 100h of baking at 150°C. [Copyright &y& Elsevier]

Abstract: What effect Zr and Ti source materials had on the conformality of film thickness and composition inside trench substrates was investigated for MOCVD-Pb(Zr,Ti)O3 thin films deposited by three kinds of source systems. The dependence of the deposition rate on temperature could almost be divided into two deposition–temperature regions and their boundary temperatures depended on the source systems used. The conformality of film thickness and composition also depended on the source systems, which indicated how important the selection of the source materials system was. We found that a source system of Pb(C11H19O2)2–Zr(O(CH3)2CH2CH2OCH3)4–Ti(OC(CH3)2CH2OCH3)4–O2 was the most suited to obtain uniform film thickness and composition over a wide range of deposition temperatures. [Copyright &y& Elsevier]