Pre-integrated non-equilibrium combustion-response mapping for internal combustion engine emissions

This study establishes a novel method to predict emissions in internal combustion (IC) engines. The method couples a multi-dimensional engine modeling program with pre-integrated non-equilibrium chemical kinetic reaction results. Prior to engine simulation, detailed chemical kinetic reactions of air/fuel mixtures at different temperatures, pressures, and compositions, which possibly occur in the IC engine, are calculated using SENKIN, a subprogram in CHEMKIN-II computer package [1]. The reaction results are decoupled from their chemical eigenvalue (order of about 10-10s) then integrated and saved in physical timescale (order of about 10-5 s) in a database file. In the database, reaction results of different initial conditions (temperature, pressure, and composition) are stored in different zones; the zones are indexed using their respective reaction conditions. In the modeling process, fluid and thermal dynamics, movement of piston and valves, and spray droplets interaction are simulated by KIVA-3V [2] using the finite- volume technique. During combustion of the air/fuel mixture, instead of calculating directly the non-equilibrium chemical reactions, reaction results are obtained from the database file. KIVA-3V sends a request, with inputs of temperature, pressure, composition, and reaction time of combustible mixture to an interpolating subroutine. This interpolating subroutine uses these reaction conditions as indices to lookup the requested results in the database file, then returns temperature, heat release, and species concentrations after reaction to the main program. The approach avoids direct time consuming calculation of detailed chemical reactions as well as the errors introduced by coupling the physical and chemical processes. which have different eigenvalues. The required computational effort is shortened. Emissions are predicted accurately since reaction of air/fuel mixture is calculated using the detailed kinetics mechanism. The database file for each fuel must be generated once, and can be used for any application which requires chemical reactions of this fuel. The approach is applied to model a Caterpillar 3401 direct injection (DI) compression ignition (C1) Diesel engine, a Rover K4 methane-fuelled spark ignition (SI) engine, a Ricardo E6 co-operative fuel research (CFR) SI gasoline engine, and a Toledo 1500 four-stroke SI gasoline engine. Predicted results agree well with the experimental data

Research on the stability of the 3D frame on coral foundation subjected to impact load

This article presents an application of the finite element method (FEM) for the stability analysis of 3D frame (space bar system) on the coral foundation impacted by collision impulse. One-way joints between the rod and the coral foundation are described by the contact element. Numerical analysis shows the effect of some factors on the stability of the bar system on coral foundation. The results of this study can be used for stability analysis of the bar system on coral foundation subjected to sea wave load

Static and Dynamic Analysis of Piezoelectric Laminated Composite Beams and Plates

In this chapter, the mechanical behavior analysis of piezoelectric laminated composite beams and plates is influenced subjected to static, dynamic, and aerodynamic loads. Algorithm for dynamic, stability problem analysis and vibration control of laminated composite beams and plates with piezoelectric layers is presented. In addition, numerical calculations, considering the effect of factors on static, dynamic, and stability response of piezoelectric laminated composite beams and plates are also clearly presented. The content of this chapter can equip readers with the knowledge used to calculate the static, dynamic, and vibration control of composite beams, panels made of piezoelectric layers applied in the field different techniques

Dynamic stability analysis of laminated composite plates with piezoelectric layers

Research on the stability to determine the critical value of structures is a complex issue but of real significance. Piezoelectric composite plate is one of the structures which have the ability to control the mechanical behaviors under loads. One of the prominent capabilities of this structure is the ability to control its vibration and stability. Using the finite element method (FEM) and construction calculation program in Matlab, the authors analyzed the elastic stability of piezoelectric composite plates under dynamic in-plane loads, taking into account damping properties of the structure. Critical loads and other factors affecting the stability of the plate are investigated

Tranexamic acid for intracerebral haemorrhage within 2 hours of onset : protocol of a phase II randomised placebo-controlled double-blind multicentre trial

Rationale Haematoma growth is common early after intracerebral haemorrhage (ICH), and is a key determinant of outcome. Tranexamic acid, a widely available antifibrinolytic agent with an excellent safety profile, may reduce haematoma growth. Methods and design Stopping intracerebral haemorrhage with tranexamic acid for hyperacute onset presentation including mobile stroke units (STOP-MSU) is a phase II double-blind, randomised, placebo-controlled, multicentre, international investigator-led clinical trial, conducted within the estimand statistical framework. Hypothesis In patients with spontaneous ICH, treatment with tranexamic acid within 2 hours of onset will reduce haematoma expansion compared with placebo. Sample size estimates A sample size of 180 patients (90 in each arm) would be required to detect an absolute difference in the primary outcome of 20% (placebo 39% vs treatment 19%) under a two-tailed significance level of 0.05. An adaptive sample size re-estimation based on the outcomes of 144 patients will allow a possible increase to a prespecified maximum of 326 patients. Intervention Participants will receive 1 g intravenous tranexamic acid over 10 min, followed by 1 g intravenous tranexamic acid over 8 hours; or matching placebo. Primary efficacy measure The primary efficacy measure is the proportion of patients with haematoma growth by 24 +/- 6 hours, defined as either >= 33% relative increase or >= 6 mL absolute increase in haematoma volume between baseline and follow-up CT scan. Discussion We describe the rationale and protocol of STOP-MSU, a phase II trial of tranexamic acid in patients with ICH within 2 hours from onset, based in participating mobile stroke units and emergency departments.Peer reviewe

Spatial Organization and Molecular Correlation of Tumor-Infiltrating Lymphocytes Using Deep Learning on Pathology Images

Beyond sample curation and basic pathologic characterization, the digitized H&E-stained images of TCGA samples remain underutilized. To highlight this resource, we present mappings of tumorinfiltrating lymphocytes (TILs) based on H&E images from 13 TCGA tumor types. These TIL maps are derived through computational staining using a convolutional neural network trained to classify patches of images. Affinity propagation revealed local spatial structure in TIL patterns and correlation with overall survival. TIL map structural patterns were grouped using standard histopathological parameters. These patterns are enriched in particular T cell subpopulations derived from molecular measures. TIL densities and spatial structure were differentially enriched among tumor types, immune subtypes, and tumor molecular subtypes, implying that spatial infiltrate state could reflect particular tumor cell aberration states. Obtaining spatial lymphocytic patterns linked to the rich genomic characterization of TCGA samples demonstrates one use for the TCGA image archives with insights into the tumor-immune microenvironment

Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas

Although theMYConcogene has been implicated incancer, a systematic assessment of alterations ofMYC, related transcription factors, and co-regulatoryproteins, forming the proximal MYC network (PMN),across human cancers is lacking. Using computa-tional approaches, we define genomic and proteo-mic features associated with MYC and the PMNacross the 33 cancers of The Cancer Genome Atlas.Pan-cancer, 28% of all samples had at least one ofthe MYC paralogs amplified. In contrast, the MYCantagonists MGA and MNT were the most frequentlymutated or deleted members, proposing a roleas tumor suppressors.MYCalterations were mutu-ally exclusive withPIK3CA,PTEN,APC,orBRAFalterations, suggesting that MYC is a distinct onco-genic driver. Expression analysis revealed MYC-associated pathways in tumor subtypes, such asimmune response and growth factor signaling; chro-matin, translation, and DNA replication/repair wereconserved pan-cancer. This analysis reveals insightsinto MYC biology and is a reference for biomarkersand therapeutics for cancers with alterations ofMYC or the PMN