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Blockchain-based publishing layer for the Keyless Signing Infrastructure

A Keyless Signing Infrastructure (KSI) provides users with a means to timestamp documents on a per-second basis. The KSI consists of a global infrastructure with several server layers and by using Merkle hash trees, the root hash can be used to verify the integrity and timestamp of a document. Regular publication of root hashes, e.g., once per month, allows a document to be verified without suppor

From performance management to managing performance : An embedded case study of the drivers of individual- and group-based performance in a call center context

Managing performance is critical for realizing certain economic benefits when managing customer relations in call centers. However, prior call center research is fragmented and under-analyzed, which contributes to a limited understanding of the underlying elements for performance and complexities in managing individual- and group-based performance in call centers. The purpose of this thesis is to

Head Movement Compensation and Multi-Modal Event Detection in Eye-Tracking Data for Unconstrained Head Movements

BackgroundThe complexity of analyzing eye-tracking signals increases as eye-trackers become more mobile. The signals from a mobile eye-tracker are recorded in relation to the head coordinate system and when the head and body move, the recorded eye-tracking signal is influenced by these movements, which render the subsequent event detection difficult.New methodThe purpose of the present paper is to

Adsorption and Reaction of CO and NO on Ir(111) under Near Ambient Pressure Conditions

The adsorption and reaction of CO and NO on Ir(111) have been studied by near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) together with low-energy electron diffraction, scanning tunneling microscopy, and mass spectroscopy (MS). Under both ultrahigh vacuum (UHV) and NAP conditions CO molecules occupy on-top sites of the Ir(111) surface at room temperature (RT) by forming two-dimensi

Temperature imaging in low-pressure flames using diode laser two-line atomic fluorescence employing a novel indium seeding technique

The use of diode lasers for spatially resolved temperature imaging is demonstrated in low-pressure premixed methane–air flames using two-line atomic fluorescence of seeded indium atoms. This work features the advantages of using compact diode lasers as the excitation sources with the benefits of two-dimensional planar imaging, which is normally only performed with high-power pulsed lasers. A versa

Integrated conodont biostratigraphy and carbon isotope chemostratigraphy in the Lower–Middle Ordovician of southern Sweden reveals a complete record of the MDICE

One of the few and most complete records of the MDICE (Middle Darriwilian Isotope Carbon Excursion) is herein documented from Baltoscandia. Based on a core section penetrating the condensed Lower–Middle Ordovician succession (~46 m) on the island of Öland, southeastern Sweden, we provide an integrated scheme for carbon isotope chemostratigraphy (313 samples) and conodont biostratigraphy (29 sample

A Simple Method for Subspace Estimation with Corrupted Columns

This paper presents a simple and effective way of solving the robust subspace estimation problem where the corruptions are column-wise. The method we present can handle a large class of robust loss functions and is simple to implement. It is based on Iteratively Reweighted Least Squares (IRLS) and works in an iterative manner by solving a weighted least-squares rank-constrained problem in every it

A characterization of optimal base-stock levels for a multistage serial supply chain

In this article, we present a multistage model to optimize inventory control decisions under stochastic demand and continuous review. We first formulate the general problem for continuous stages and use a decomposition solution approach: since it is never optimal to let orders cross, the general problem can be broken into a set of single-unit subproblems that can be solved in a sequential fashion.

Manipulation of the spatial distribution of laser-accelerated proton beams by varying the laser intensity distribution

We report on a study of the spatial profile of proton beams produced through target normal sheath acceleration using flat target foils and changing the laser intensity distribution on the target front surface. This is done by either defocusing a single laser pulse or by using a split-pulse setup and irradiating the target with two identical laser pulses with variable spatial separation. The result

Towards a physics-based multiscale modelling of the electro-mechanical coupling in electro-active polymers

Owing to the increasing number of industrial applications of electro-active polymers (EAPs), there is a growing need for electromechanical models which accurately capture their behaviour. To this end, we compare the predicted behaviour of EAPs undergoing homogeneous deformations according to three electromechanical models. The first model is a phenomenological continuumbased model composed of the

Investigation of ionization-induced electron injection in a wakefield driven by laser inside a gas cell

Ionization-induced electron injection was investigated experimentally by focusing a driving laser pulse with a maximum normalized potential of 1.2 at different positions along the plasma density profile inside a gas cell, filled with a gas mixture composed of 99%H2+1%N2. Changing the laser focus position relative to the gas cell entrance controls the accelerated electron bunch properties, such as

Which agricultural management interventions are most influential on soil organic carbon (using time series data)?

Background: Loss of soil organic carbon (SOC) from agricultural land is identified as one of the major threats to soils, as it influences both fertility and the production of ecosystem services from agriculture. Losses of SOC across regions are often determined by monitoring in different land use systems. Results from agricultural field experiments can reveal increasing SOC stocks after implementa

Utrymning och tekniska installationer i vägtunnlar med dubbelriktad trafik

The report provides an overview of human behaviour in tunnel fires in single tube road tunnels. The behaviour is linked to the concept of a behaviour sequences presented by Canter et al. (1980). The main focus has been to present relevant research and findings provided in accident investigation reports mainly for long and steep sub-sea tunnels designed according to the self-rescue principle. Resea

How does tillage intensity affect soil organic carbon? A systematic review protocol

Background: Soils contain the greatest terrestrial carbon (C) pool on the planet. Since approximately 12 % of soil C is held in cultivated soils, management of these agricultural areas has a huge potential to affect global carbon cycling; acting sometimes as a sink but also as a source. Tillage is one of the most important agricultural practices for soil management and has been traditionally under

Climate, CO2 and human population impacts on global wildfire emissions

Wildfires are by far the largest contributor to global biomass burning and constitute a large global source of atmospheric traces gases and aerosols. Such emissions have a considerable impact on air quality and constitute a major health hazard. Biomass burning also influences the radiative balance of the atmosphere and is thus not only of societal, but also of significant scientific interest. Ther

Scale-invariant nonlinear optics in gases

Nonlinear optical methods have become ubiquitous in many scientific areas, from fundamental studies of timeresolved electron dynamics to microscopy and spectroscopy applications. They are, however, often limited to a certain range of parameters such as pulse energy and average power. Restrictions arise from, for example, the required field intensity as well as from parasitic nonlinear effects and

Prioritization guidelines for green food packaging development

Purpose: Current literature emphasizes using a holistic perspective on green packaging development (GPD) as an important strategy for reducing the environmental impact of products’ supply chain (SC). In practice, however, it can be difficult for packaging developers to strike a balance between all the different environmental requirements on packaging, and trade-offs are common. Life cycle assessme