Benedikt Christoph Wolters

Cloudflare

CAPTCHAs are necessary to protect websites from bots and malicious crawlers, yet are increasingly solvable by automated systems. This has led to more challenging tests that require greater human effort and cultural knowledge; they may prevent bots effectively but sacrifice usability and discourage the human users they are meant to admit. We propose...

HTTP/2 supersedes HTTP/1.1 to tackle the performance challenges of the modern Web. A highly anticipated feature is Server Push, enabling servers to send data without explicit client requests, thus potentially saving time. Although guidelines on how to use Server Push emerged, measurements have shown that it can easily be used in a suboptimal way an...

HTTP/2 was recently standardized to optimize the Web by promising faster Page Load Times (PLT) as compared to the widely deployed HTTP/1.1. One promising feature is HTTP/2 server push, which turns the former pull-only into a push-enabled Web. By enabling servers to preemptively push resources to the clients without explicit request, it promises fur...

Abstract—The simplicity of HTTP made it the default building block for desktop and mobile apps, yet it suffers from inherent inefficiencies in the modern web. HTTP/2 was designed to address these inefficiencies and its adoption remarks a major protocol shift in the Internet. Despite this relevance, its Internet-wide adoption remains unknown. Especi...

In this paper we address the safety analysis of chemical plants controlled by programmable logic controllers (PLCs). We consider a specification of the control program of the PLCs, extended with the specification of the dynamic plant behavior. The resulting hybrid models can be transformed to hybrid automata, for which advanced techniques for reach...

Genetic algorithms have been applied to various optimization problems in the past. Our library GeneiAL implements a framework for genetic algorithms specially targeted to the area of hybrid electric vehicles. In a parallel hybrid electric vehicle (PHEV), an internal combustion engine and an electrical motor are coupled on the same axis in parallel....

Abstract: Hybrid electric vehicles use control strategies to distribute the torque requested by the driver between the internal combustion engine and the electrical motor. Many different types of control strategies have been proposed, but in general it is impossible to determine which control strategy performs best if the future driving conditions...

In this paper we address the safety analysis of chemical plants controlled by programmable logic controllers (PLCs). We consider sequential function charts (SFCs) for the programming of the PLCs, extended with the specification of the dynamic plant behavior. The resulting hybrid SFC models can be transformed to hybrid automata, opening the way to t...