The aim of this study was to obtain a greater insight into the association between vacations and happiness. We examined whether vacationers differ in happiness, compared to those not going on holiday, and if a holiday trip boosts post-trip happiness. These questions were addressed in a pre-test/post-test design study among 1,530 Dutch individuals. 974 vacationers answered questions about their ...

Round-trip engineering is a challenging task that will become an important enabler for many Model-Driven Software Development approaches. Model round-trip engineering involves synchronizing models and keeping them consistent, thus enabling the software engineer to freely move between different representations. This vision of complete round-trip engineering is only realized to a limited degree i...

This paper explores interoperability for data represented using the Graph Annotation Framework (GrAF) (Ide and Suderman, 2007) and the data formats utilized by two general-purpose annotation systems: the General Architecture for Text Engineering (GATE) (Cunningham et al, 2002) and the Unstructured Information Management Architecture (UIMA) (Ferrucci and Lally, 2004). GrAF is intended to serve a...

We propose two methods to passively measure and monitor changes in round-trip times (RTTs) throughout the lifetime of a TCP connection. Our first method associates data segments with the acknowledgments (ACKs) that trigger them by leveraging the TCP timestamp option. Our second method infers TCP RTT by observing the repeating patterns of segment clusters where the pattern is caused by TCP selfc...

We develop an easy to use demand estimation strategy for multi-site trips within a stated preference framework. With this model, we evaluate: 1) changes in the marginal value of onsite time, 2) changes in the marginal value of total time in the tour package, 3) changes in both the number and types of sites on consumer surplus, 4) changes in the variable costs of onsite time on the elasticity of...

Model management is a new approach to meta data management that offers a higher level programming interface than current techniques. The main abstractions are models (e.g., schemas, interface definitions) and mappings between models. It treats these abstractions as bulk objects and offers such operators as Match, Merge, Diff, Compose, Apply, and ModelGen. This paper extends earlier treatments o...

Modern TRIP assisted steels contain retained austenite with carbon concentrations in excess of 1 wt-%. Some of their mechanical properties, in particular the toughness and ductility, rely on the diffusionless transformation of this austenite into high-carbon martensite, induced by stress and strain. The properties can be excellent in spite of the fact that freshly formed high-carbon martensite ...

Brassinosteroids (BRs) regulate multiple aspects of plant growth and development and require an active BRASSINOSTEROID-INSENSITIVE 1 (BRI1) receptor serine/threonine kinase for hormone perception and signal transduction. In mammals, the transforming growth factor-beta (TGF-beta) family of polypeptides modulate numerous aspects of development and are perceived at the cell surface by a complex of...

P2P video streaming is receiving enormous attention, and when video is involved, the efficient use of the network becomes a very important issue, specially if live applications are addressed. In this work we study properties of Push/Pull protocols for the exchange of video chunks in non-structured systems. Push/Pull protocols are a broad class of chunk exchange mechanisms where peers alternate ...