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Adolescent problem behaviour : The gender gap in European perspective

This study scrutinizes gender differences in adolescent problem behaviour and its potential determinants, simultaneously taking into account the individual and contextual level, including personality, family and country characteristics. Using the 2010 EU Kids Online Survey, we estimate multilevel models on 18,027 individuals from 24 European countries. In line with earlier research, we find that b

Tools for Road Safety Audits and Road Safety Inspections at Work Zones

Road Safety Audits (RSA) and Road Safety Inspections (RSI) are effective means of Road Infrastructure Safety Management. They are preventive tools, consisting of systematic, safety assessments, carried out by trained, independent safety expert teams, resulting in a formal report on detected road hazards and safety issues, requiring a formal response by the relevant road authority. Yet, current reg

Transverse RF Deflecting Structures for the MAX IV LINAC

The MAX IV LINAC operates both as a full-energy injector for two electron storage rings, and as a driver for a Short Pulse Facility (SPF). Recently a conceptual design report for a Soft X-ray Laser (SXL) beamline at the end of the existing LINAC was started. For SPF and SXL operation, it is important to characterize beam parameters such as bunch profile, slice energy spread and slice emittance. Fo

Experience and initial measurements of magnetic linearisation in the MAX IV linac bunch compressors

The MAX IV Linac is now in routine operation for injection into two storage rings, and as a high-brightness driver for a Short Pulse Facility (SPF). In short-pulse mode the electron bunch is created in a photo cathode gun and compressed in two double achromat bunch compressors that also linearise longitudinal phase space with the second order transfer matrix element T566. T566 in the compressors c

Color reconnections and rapidity gaps

I argue that the success of recently proposed models describing events with large rapidity gaps in DIS at HERA in terms of non-perturbative colour exchange is heavily reliant on suppression of perturbative gluon emission in the proton direction. There is little or no physical motivation for such suppression and I show that a model without this suppression cannot describe the rapidity gap events at

Reconnecting colored dipoles

Reconnections among the produced colour dipoles in the Dipole Cascade Model are discussed, and an implementation in theAriadne program is presented. The reconnections are shown to have only small effects on event shapes at LEP 1, on theW mass determination at LEP 2 and on rapidity gaps in deep inelastic scattering at HERA.

School-based study found that physical activity and aerobic fitness predicted increases in total body fat and abdominal fat at a mean age of 9.8 years.

AIM: We assessed whether baseline measurements of physical activity, aerobic fitness, body fat and abdominal fat were predictors of changes in body fat measurements over a two-year period.METHODS: The study comprised of 204 children aged 9.8 ± 0.6 years with a normal body mass distribution, who recruited from four schools in middle-class areas of Malmö, Sweden, from 2001 to 2004. Peak oxygen uptak

Real-Time Calibration of Planar Laser Induced Fluorescence Air/Fuel-Ration Measurements in Combustion Environments Using in-situ Raman Scattering

A laser-based technique for recording absolute air-fuel ratio maps in a single-laser pulse in combustion devices, for instance, prior to ignition in internal combustion engines, is demonstrated. The method is based on an in situ pulse-to-pulse calibration of two-dimensional laser-induced fluorescence (LIF) images of relative fuel distributions by a point Raman measurement. A single excimer laser p

Small x effects in W + jets production at the Tevatron

The jet structure in events with Drell-Yan-produced W bosons is discussed, and a new model for describing such an event is presented. The model is shown to explain recent measurements of the W-jet rapidity correlation and predicts a transverse energy flow at high W rapidities (corresponding to probing small-x partons in one of the incoming protons) higher than conventional parton cascade event gen

Engine Diagnostics Using Laser Induced Fluorescence Signals Collected Through an Endoscopic Detection System

In this paper an alternative method for collecting laser induced fluorescence (LIF) signals from engines with limited optical access is presented. An endoscopic detection system has been used for LIF visualisation of both gaseous and liquid fluids in a DISI-engine. The use of an endoscope made it possible to monitor parts of the combustion chamber that could not be accessed through the piston with

Recognition in Human–Robot Interaction : The gateway to engagement

We argue that mutually adaptive interaction involves the robot as a partner as opposed to a tool, and requires that the robot is susceptible to similar environmental cues and behaviour patterns as humans are. Recognition, or the acknowledgement of the other as individual, is fundamental to mutually adaptive interaction. Recognition leads to a dynamic coupling of human and robot such that they beco

Investigation of the Fuel Distribution and the In-Cylinder Flow Field in a Stratified Charge Engine Using Laser Techniques and Comparison with CFD-Modelling

This paper presents an investigation of a Volvo Direct Injection Spark Ignition (DISI) engine, where the fuel distribution and the in-cylinder flow field have been mapped by the use of laser techniques in an engine with optical access. Along with the experimental work, CFD-modelling of flow and fuel distribution has been performed.Laser Induced Fluorescence (LIF) visualisation of the fuel distribu

A study of the Homogeneous Charge Compression Ignition combustion process by chemiluminescence imaging

An experimental study of the Homogeneous Charge Compression Ignition (HCCI) combustion process has been conducted by using chemiluminescence imaging. The major intent was to characterize the flame structure and its transient behavior. To achieve this, time resolved images of the naturally emitted light were taken. Emitted light was studied by recording its spectral content and applying different f