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Direct test of time reversal symmetry in the entangled neutral kaon system at a ϕ-factory

We present a novel method to perform a direct T (time reversal) symmetry test in the neutral kaon system, independent of any CP and/or CPT symmetry tests. This is based on the comparison of suitable transition probabilities, where the required interchange of in ↔ out states for a given process is obtained exploiting the Einstein–Podolski–Rosen correlations of neutral kaon pairs produced at a ϕ-fac

Consistent probabilistic description of the neutral Kaon system

The neutral Kaon system has both CP violation in the mass matrix and a non-vanishing lifetime difference in the width matrix. This leads to an effective Hamiltonian which is not a normal operator, with incompatible (non-commuting) masses and widths. In the Weisskopf–Wigner Approach (WWA), by diagonalizing the entire Hamiltonian, the unphysical non-orthogonal “stationary” states KL,S are obtained.

Remote Supervision of an Autonomous Surface Vehicle using Virtual Reality

We compared three different Graphical User Interfaces (GUI) that we have designed and implemented to enable human supervision of an Autonomous Surface Vehicle (ASV). Special attention has been paid to provide tools for a safe navigation and giving the user a good overall understanding of the surrounding world while keeping the cognitive load at a low level. Our findings indicate that a GUI in 3D,

Patients in Clinical Cancer Trials. Information, Understanding and Decision-Making

The informed consent process for clinical trials (CTs) is complex. Patients must be able to understand the information given to be able to make an informed decision. This thesis aimed to explore patients’ and patient representatives’ views, factual knowledge, and perceived understanding of patient information in clinical cancer trials, and to investigate how patients’ understanding may be correlat

SEDGE : Symbolic example data generation for dataflow programs

Exhaustive, automatic testing of dataflow (esp. mapreduce) programs has emerged as an important challenge. Past work demonstrated effective ways to generate small example data sets that exercise operators in the Pig platform, used to generate Hadoop map-reduce programs. Although such prior techniques attempt to cover all cases of operator use, in practice they often fail. Our SEDGE system addresse

Program metamorphosis

Modern development environments support refactoring by providing atomically behaviour-preserving transformations. While useful, these transformations are limited in three ways: (i) atomicity forces transformations to be complex and opaque, (ii) the behaviour preservation requirement disallows deliberate behaviour evolution, and (iii) atomicity limits code reuse opportunities for refactoring implem

Residual investigation : Predictive and precise bug detection

We introduce the concept of "residual investigation" for program analysis. A residual investigation is a dynamic check installed as a result of running a static analysis that reports a possible program error. The purpose is to observe conditions that indicate whether the statically predicted program fault is likely to be realizable and relevant. The key feature of a residual investigation is that

Second-order constraints in dynamic invariant inference

The current generation of dynamic invariant detectors often produce invariants that are inconsistent with program semantics or programmer knowledge. We improve the consistency of dynamically discovered invariants by taking into account higher-level constraints. These constraints encode knowledge about invariants, even when the invariants themselves are unknown. For instance, even though the invari

Java wildcards meet definition-site variance

Variance is concerned with the interplay of parametric polymorphism (i.e., templates, generics) and subtyping. The study of variance gives answers to the question of when an instantiation of a generic class can be a subtype of another. In this work, we combine the mechanisms of use-site variance (as in Java) and definition-site variance (as in Scala and C#) in a single type system, based on Java.

Analysis of imperative XML programs

The widespread adoption of XML has led to programming languages that support XML as a first class construct. In this paper, we present a method for analyzing and optimizing imperative XML processing programs. In particular, we present a program analysis, based on a flow-sensitive type system, for detecting both redundant computations and redundant traversals in such programs. The analysis handles

Developing and debugging algebraic specifications for Java classes

Modern programs make extensive use of reusable software libraries. For example, a study of a number of large Java applications shows that between 17% and 30% of the classes in those applications use container classes defined in the java.util package. Given this extensive code reuse in Java programs, it is important for the interfaces of reusable classes to be well documented. An interface is well

Analysis of imperative XML programs

The widespread adoption of XML has led to programming languages that support XML as a first class construct. In this paper, we present a method for analyzing and optimizing imperative XML processing programs. In particular, we present a program analysis, based on a flow-sensitive type system, for detecting both redundant computations and redundant traversals in XML processing programs. The analysi

Discovering documentation for Java container classes

Modern programs make extensive use of reusable software libraries. For example, we found that 17% to 30% of the classes in a number of large Java applications use the container classes from the java.util package. Given this extensive code reuse in Java programs, it is important for the reusable interfaces to have clear and unambiguous documentation. Unfortunately, most documentation is expressed i

Opinion Polarity Identification of Movie Reviews

One approach to the assessment of overall opinion polarity (OvOP) of reviews, a concept defined in this paper, is the use of supervised machine learning mechanisms. In this paper, the impact of lexical feature selection and feature generalization, applied to reviews, on the precision of two probabilistic classifiers (Naïve Bayes and Markov Model) with respect to OvOP identification is observed. Fe

Double Compression-Expansion Engine Concepts : Experimental and simulation study of a split-cycle concept for improved brake efficiency

The four-stroke engine was invented by Nikolaus Otto during the second half of the 19th century. Although a lot of technological improvements have been made over the years, the operating principle with four-strokes remains the same. The need and desire of engines with even higher fuel-efficiency is a motivation to study alternative engine concepts. This thesis presents studies of the Double Compre

Emulsion Formation by Homogenization : Current Understanding and Future Perspectives

Emulsion formation by homogenization is commonly used in food production and research to increase product stability and to design colloidal structures. High-energy methods such as high-pressure homogenizers and rotor–stator mixers are the two most common techniques. However, to what extent does the research community understand the emulsion formation taking place in these devices? This contributioEmulsion formation by homogenization is commonly used in food production and research to increase product stability and to design colloidal structures. High-energy methods such as high-pressure homogenizers and rotor-stator mixers are the two most common techniques. However, to what extent does the research community understand the emulsion formation taking place in these devices? This contributio

Appraisal of strategies to improve thermophilic hydrogen production exploiting Caldicellulosiruptor species

The transition from a fossil to a bio-based economy is of vital importance to stem the effects of ongoing climate change.This bio-based economy will necessitate the production of both biofuels and chemical compounds from biologicalsources. Hydrogen is a promising candidate as a renewable energy carrier due to its high energy density, carbonneutrality when combusted and its potential use as a reduc