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System Simulation of Partially Premixed Combustion in Heavy-Duty Engines : Gas Exchange, Fuels and In-cylinder Analysis

The concept of partially premixed combustion (PPC), applied to conventional diesel engines, has shown to yield high gross efficiencies and low emissions of oxides of nitrogen and soot. PPC emerged from the knowledge gained from homogeneous charge compression ignition (HCCI) research. To extend the load range and thus reduce cylinder pressure rise rates, the fuel is directly injected during the comThe concept of partially premixed combustion (PPC), applied to conventional diesel engines, has shown to yield high gross efficiencies and low emissions of oxides of nitrogen and soot. PPC emerged from the knowledge gained from homogeneous charge compression ignition (HCCI) research. To extend the load range and thus reduce cylinder pressure rise rates, the fuel is directly injected during the com

Plant survival in Iceland during periods of glaciation?

Aim: The paper addresses the classical question of possible plant survival in Iceland during the last glacial period in the light of a palaeobotanical record from northern Iceland, spanning the period 11,300-9000 BP, including the Younger Dryas stadial. We review the Late Cenozoic fossil plant record, the past debate on glacial plant refugia in Iceland, and the evidence for ice-free areas during t

Updated determination of chiral couplings and vacuum condensates from hadronic τ decay data

We analyze the lowest spectral moments of the left-right two-point correlation function, using all known short-distance constraints and the recently updated ALEPH V-A spectral function from τ decays. This information is used to determine the low-energy couplings L10 and C87 of chiral perturbation theory and the lowest-dimensional contributions to the operator product expansion of the left-right co

Color structure for soft gluon resummation: A General recipe

A strategy for calculating the color structure needed for soft gluon resummation for processes with any number of colored partons is introduced using a Nc → ∞inspired basis. In this basis a general formalism can be found at the same time as the calculations are simplified.The advantages are illustrated by recalculating the soft anomalous dimension matrix for the processes gg → gg, qq → qqg and qq

Delta 2.0 - A program for finding dependencies in tables of data

A package written in C for identifying variable dependencies in tables of data is presented. The key ingredient is the δ-test, which establishes dependency structures by exploiting the properties of continuous functions using conditional probabilities formed out of the data. The method estimates most relevant variables, embedding dimensions and noise levels. The program, which is self-contained, a

Solving optimization problems with mean field methods

A brief review is given for the use of feed-back artificial neural networks (ANN) to obtain good approximate solutions to combinatorial optimization problems. The key element is the mean field approximation (MFT), which differs from conventional methods and "feels" its ways towards good solutions rather than fully or partly exploring different possible solutions. The methodology, which is illustra

Mass reconstruction with a neural network

A feed-forward neural network method is developed for reconstructing the invariant mass of hadronic jets appearing in a calorimeter. The approach is illustrated in W→qq, where W-bosons are produced in pp reactions at SPS collider energies. The neural network method yields results that are superior to conventional methods. This neural network application differs from the classification ones in the

The finite temperature phase transition in four flavour QCD on an 8×12 3 lattice

We present results of a numerical study of lattice QCD with four dynamical flavours of staggered fermions, performed by using a hybrid Monte Carlo algorithm on an 8×12 3 lattice. We find a rapid change in the average value of the Polyakov loop at β c =5.25±0.025 for a quark mass ma=0.025; at this mass value, the behaviour of the chiral order parameter, 〈ΨΨ〉 does not yet allow an independent deter

Experimental and Numerical Investigations of Heat Transfer related to Gas Turbine Applications

Gas turbines are broadly used in aerospace and marine propulsion and power production etc.Investigation of heat transfer in gas turbines is a long-lasting and still an active subject ofresearch due to its tremendous importance. Thermal efficiency, durability and fatigue lifetimeof a gas turbine greatly rely on the heat transfer characteristics of gas turbine components.According to the first law o

The axial anomaly and the lattice Dirac sea

In the hamiltonian formulation of fermions coupled to external gauge fields, the axial anomaly has a simple physical interpretation in terms of level shifting at the top of the Dirac sea. We apply this formalism to lattice QED in 1 + 1 and 3 + 1 dimensions, in order to study how the lattice regulation and small fermion mass affect the picture. For a simple choice of the E and B fields, it is possi

Purification and retention of sucrose in sugar beet molasses by utilizing ceramic nanofiltration membranes

Biorefineries are rapid growing branches in the world of sustainable chemical engineering, and one aspect that becomes more and more important is the reuse and valorization of different by-products. In sugar mills, molasses is a low value by-product mainly used for animal feed. However, a large part of the molasses contains the main product of the sugar mill: sucrose. By using membrane filtration,

Exploring Shared-Bike Travel Patterns Using Big Data: Evidence in Chicago and Budapest

Bike-sharing systems are an emerging form of sharing-mobility in manycities worldwide. The travel patterns of users that take advantage of smart devices to ride a shared-bicycle in two large cities (Chicago and Budapest) have been investigated, with analysis of approximately two million transaction data records associated with bike trips made over a three-month period in each location. Several asp

Osynliga pengar : Kulturella perspektiv på ett kontantlöst samhälle

I texten diskuteras vilka kulturella och sociala konsekvenser en snabb tillbakagång för kontanter till fördel för andra betalningssätt kan komma att få. Vem riskerar att lämnas utanför en snabb digital utveckling och hur förändras pengars kulturella och symboliska mening?

Industrial applications of ultrafiltration in the pharmaceutical biotechnology

In pharmaceutical biotechnology, ultrafiltration with diafiltration for recovery of fermentation products on an industrial scale is now the state-of-the-art technology. To optimise this process, DSS has developed two new concepts: (1) an optimised control system for constant permeate concentration even at varying feed streams and (2) continuous counter-current diafiltration to significantly reduce

Osteopontin mediates murine transfusion-related acute lung injury through stimulation of pulmonary neutrophil accumulation.

Transfusion-related acute lung injury (TRALI) is one of the leading causes of transfusion-related fatalities and is characterized by the onset of acute respiratory distress within 6 hours of a blood transfusion. There are no specific therapies available and the pathogenesis remains unclear. Pre-existing inflammation is a risk factor for TRALI and neutrophils (PMNs) are considered to be the major p

UV and IR Absorption Cross-sections of HCHO, HCDO, and DCDO

UV (240-370 nm) and IR (3200-1500 cm-1) absorption cross-sections of HCHO, HCDO, and DCDO in abath gas of N2 at atmospheric pressure and 296 K are reported from simultaneous measurements in the twospectral regions. Cross-sections were placed on an absolute scale through quantitative conversion offormaldehyde to CO and HCOOH by titration with Br atoms, also monitored by FTIR. The integrated UVabsor

Atmospheric chemistry of cis-CF3CHCHF: Kinetics of reactions with OH radicals and O3 and products of OH radical initiated oxidation

Long path length FTIR-smog chamber techniques were used to measure k(OH + cis-CF3CHCHF) = (1.20 ± 0.14) × 10−12 and k(O3 + cis-CF3CHCHF) = (1.65 ± 0.16) × 10−21 cm3 molecule −1 s−1 in 700 Torr of N2/O2 diluent at 296 K. The OH initiated oxidation of cis-CF3CHCHF gives CF3CHO and HCOF in molar yields which are indistinguishable from 100%. The atmospheric lifetime of cis-CF3CHCHF is determined by it

A tale of 24 counties? Regional variation in female labour force participation in Sweden, 1870-1950

Female labor force participation increased significantly during the 20thcentury, not least in Sweden. In this paper, we investigate the importance of economic, demographic and sociocultural factors in the initial increase and growth of female labor force participationover the course of industrializationusing county-level data and panel regressions.There were important spatial differences across co

Twisted Ribbon Aggregates in a Model Peptide System

The model peptides A 8 K and A 10 K self-assemble in water into ca. 100 nm long ribbon-like aggregates. These structures can be described as β-sheets laminated into a ribbon structure with a constant elliptical cross-section of 4 by 8 nm, where the longer axis corresponds to a finite number, N ≠15, of laminated sheets, and 4 nm corresponds to a stretched peptide length. The ribbon cross-section