A novel network architecture for train-to-wayside communication with quality of service over heterogeneous wireless networks

In the railway industry, there are nowadays different actors who would like to send or receive data from the wayside to an onboard device or vice versa. These actors are e.g., the Train Operation Company, the Train Constructing Company, a Content Provider, etc. This requires a communication module on each train and at the wayside. These modules interact with each other over heterogeneous wireless links. This system is referred to as the Train-to-Wayside Communication System (TWCS). While there are already a lot of deployments using a TWCS, the implementation of quality of service, performance enhancing proxies (PEP) and the network mobility functions have not yet been fully integrated in TWCS systems. Therefore, we propose a novel and modular IPv6-enabled TWCS architecture in this article. It jointly tackles these functions and considers their mutual dependencies and relationships. DiffServ is used to differentiate between service classes and priorities. Virtual local area networks are used to differentiate between different service level agreements. In the PEP, we propose to use a distributed TCP accelerator to optimize bandwidth usage. Concerning network mobility, we propose to use the SCTP protocol (with Dynamic Address Reconfiguration and PR-SCTP extensions) to create a tunnel per wireless link, in order to support the reliable transmission of data between the accelerators. We have analyzed different design choices, pinpointed the main implementation challenges and identified candidate solutions for the different modules in the TWCS system. As such, we present an elaborated framework that can be used for prototyping a fully featured TWCS

Ontwerp en ontwikkeling van een stuur-en interface eenheid voorCCD-camera en VME-bus

SIGLEKULeuven Campusbibliotheek Exacte Wetenschappen / UCL - Université Catholique de LouvainBEBelgiu

Enhanced S-cone syndrome with preserved macular structure and severely depressed retinal function

We present ophthalmic features and genetic analysis findings of a 44-year-old croatian patient with enhanced S-cone syndrome (ESCS). Complete ophthalmic examination, Ishihara colour vision test, dark adaptometry, spectral-domain optical coherence tomography (SD-OCT), fundus autofluorescence imaging, Goldmann visual field and automated perimetry, full-field electroretinography (ERG), multifocal ERG, S-cone ERG and ON-OFF ERG were performed. Mutation screening of the NR2E3 gene, which encodes a photoreceptor-specific orphan nuclear receptor, was performed with polymerase chain reaction amplification and direct sequencing. The patient has good visual acuity and normal colour vision. Fundus examination showed normal posterior pole and nummular pigment depositions at the level of the retinal pigment epithelium in the mid-periphery of the retina. The SD-OCT images showed normal macular structure and thickness. The ERG showed characteristic findings: photopic and scotopic responses to the same stimulus had a similar waveform and were dominated by short-wavelength-sensitive mechanisms. Mutation analysis revealed the known NR2E3 mutation c.481delA (p.Thr161HisFsX18) and the novel NR2E3 variant c.1120C > T (p.Leu374Phe). To the best of our knowledge, this is the only ESCS patient older than 40 years who phenotypically has preserved macular structure, good central visual acuity and severely depressed full-field ERG as well as the first reported patient with NR2E3 mutation from Croatia