1,392 research outputs found
Influence of the isomeric composition of the acceptor on the performance of organic bulk heterojunction P3HT:bis-PCBM solar cells
We synthesized three isomeric subpopulations of bisadduct analogues of [6,6]-phenyl-C61-butyric acid methyl ester (bis-PCBM) via tether-directed control. Bulk heterojunction solar cells prepared using these isomers together with poly(3-hexylthiophene) (P3HT) resulted in an increase of Jsc from 72.4 to 79.6 A m-2, and an improvement in fill factor from 0.55 to 0.62, both with a Voc of 0.72 V resulting in an overall enhancement of the power conversion efficiency (PCE) from 2.9% to 3.5%, compared to conventional bis-PCBM.
Mining large-scale smartphone data for personality studies
In this paper, we investigate the relationship between automatically extracted behavioral characteristics derived from rich smartphone data and self-reported Big-Five personality traits (extraversion, agreeableness, conscientiousness, emotional stability and openness to experience). Our data stem from smartphones of 117 Nokia N95 smartphone users, collected over a continuous period of 17months in Switzerland. From the analysis, we show that several aggregated features obtained from smartphone usage data can be indicators of the Big-Five traits. Next, we describe a machine learning method to detect the personality trait of a user based on smartphone usage. Finally, we study the benefits of using gender-specific models for this task. Apart from a psychological viewpoint, this study facilitates further research on the automated classification and usage of personality traits for personalizing services on smartphone
Distributed Branching Bisimulation Minimization by Inductive Signatures
We present a new distributed algorithm for state space minimization modulo
branching bisimulation. Like its predecessor it uses signatures for refinement,
but the refinement process and the signatures have been optimized to exploit
the fact that the input graph contains no tau-loops.
The optimization in the refinement process is meant to reduce both the number
of iterations needed and the memory requirements. In the former case we cannot
prove that there is an improvement, but our experiments show that in many cases
the number of iterations is smaller. In the latter case, we can prove that the
worst case memory use of the new algorithm is linear in the size of the state
space, whereas the old algorithm has a quadratic upper bound.
The paper includes a proof of correctness of the new algorithm and the
results of a number of experiments that compare the performance of the old and
the new algorithms
Summary of Northern Europe as a role model:successful enterprise in a globalising economy
Does Northern Europe possess unique characteristics that cannot disappear and do not need to disappear, or will globalisation inevitably result in uniformity, divested businesses, lower wages and huge pressure on social security provisions? This is one of the main questions addressed by the authors. The authors examine how companies respond to global developments. They also discuss the implications of these developments for entrepreneurs and whether knowledge institutions and governments play a part in creating a climate that is conducive to enterprise. They consider these issues from the perspective of different regions. Each region has its own distinct regional characteristics and its own distinct regional views on particular issues. As well as endeavouring to describe the key macroeconomic characteristics, they also consider how (entrepreneurial and policy-making) organisations should respond to the current macroeconomic challenges
Determination of the trap-assisted recombination strength in polymer light emitting diodes
The recombination processes in poly(p-phenylene vinylene) based polymer light-emitting diodes (PLEDs) are investigated. Photogenerated current measurements on PLED device structures reveal that next to the known Langevin recombination also trap-assisted recombination is an important recombination channel in PLEDs, which has not been considered until now. The dependence of the open-circuit voltage on light intensity enables us to determine the strength of this process. Numerical modeling of the current-voltage characteristics incorporating both Langevin and trap-assisted recombination yields a correct and consistent description of the PLED, without the traditional correction of the Langevin prefactor. At low bias voltage the trap-assisted recombination rate is found to be dominant over the free carrier recombination rate.
Differential diagnosis of (inherited) amino acid metabolism or transport disorders
__Abstract__
Disorders of amino acid metabolism or transport are most clearly expressed in urine. Nevertheless the interpretation of abnormalities in urinary amino acid excretion remains difficult. An increase or decrease of almost every amino acid in urine can be due to various etiology. To differentiate between primary and secondary aminoacido-pathies systematic laboratory investigation is necessary. Early diagnosis of disorders of amino acid metabolism or transport is very important, because most of them can be treated, leading to the prevention of (further) clinical abnormalities. In those disorders, which cannot be treated, early diagnosis in an index-patient may prevent the birth of other siblings by means of genetic counseling and prenatal diagnosis. Primary aminoacidopathies can be due to genetically determined transport disorders and enzyme deficiencies in amino acid metabolism or degradation. Secondary aminoacidopathies are the result of abnormal or deficient nutrition, intestinal dysfunction, organ pathology or other metabolic diseases like organic acidurias. A survey of amino acid metabolism and transport abnormalities will be given, illustrated with metabolic pathways and characteristic abnormal amino acid chromatograms
ATK-ForceField: A New Generation Molecular Dynamics Software Package
ATK-ForceField is a software package for atomistic simulations using
classical interatomic potentials. It is implemented as a part of the Atomistix
ToolKit (ATK), which is a Python programming environment that makes it easy to
create and analyze both standard and highly customized simulations. This paper
will focus on the atomic interaction potentials, molecular dynamics, and
geometry optimization features of the software, however, many more advanced
modeling features are available. The implementation details of these algorithms
and their computational performance will be shown. We present three
illustrative examples of the types of calculations that are possible with
ATK-ForceField: modeling thermal transport properties in a silicon germanium
crystal, vapor deposition of selenium molecules on a selenium surface, and a
simulation of creep in a copper polycrystal.Comment: 28 pages, 9 figure
Complete genome sequences of three isolates of Xanthomonas fragariae, the bacterium responsible for angular leaf spots on strawberry plants
Xanthomonas fragariae is a worldwide spread plant bacterial disease causing angular leaf spots, and thus reducing the yield of production for strawberry fruits. Three isolates with variable geographic and time origins were sequenced with long-read technology (PacBio) to generate finished genomes of virulent strains and observe their variability in content
- …
