Rascal: A domain specific language for source code analysis and manipulation

Many automated software engineering tools require tight integration of techniques for source code analysis and manipulation. State-of-the-art tools exist for both, but the domains have remained notoriously separate because different computational paradigms fit each domain best. This impedance mismatch hampers the development of each new problem solution since desired functionality and scalability can only be achieved by repeated, ad hoc, integration of different techniques. Rascal is a domain-specific language that takes away most of this boilerplate by providing high-level integration of source code analysis and manipulation on the conceptual, syntactic, semantic and technical level. We give an overview of the language and assess its merits by implementing a complex refactoring

Rascal, 10 years later

When we designed the first version of Rascal in 2009, we jokingly promised ourselves to only write a single paper on the language itself, and see it as vehicle for research from then on,—that one paper became the SCAM 2009 article, now awarded with the SCAM most influential paper award. Since then, Rascal has evolved significantly, and has been successfully applied in research, education, and industry. This extended abstract gives an overview of the impact of Rascal over the last 10 years, and looks at current and future developments

On the impact of DSL tools on the maintainability of language implementations

Does the use of DSL tools improve the maintainability of language implementations compared to implementations from scratch? We present empirical results on aspects of maintainability of six implementations of the same DSL using different languages (Java, JavaScript, C#) and DSL tools (ANTLR, OMeta, Microsoft Oslo). Our evaluation indicates that the maintainability of language implementations is indeed higher when constructed using DSL tools

Dynamical Landau-de Gennes Theory for Electrically-Responsive Liquid Crystal Networks

Liquid crystal networks combine the orientational order of liquid crystals with the elastic properties of polymer networks, leading to a vast application potential in the field of responsive coatings, e.g., for haptic feedback, self-cleaning surfaces and static and dynamic pattern formation. Recent experimental work has further paved the way toward such applications by realizing the fast and reversible surface modulation of a liquid crystal network coating upon in-plane actuation with an AC electric field. Here, we construct a Landau-type theory for electrically-responsive liquid crystal networks and perform Molecular Dynamics simulations to explain the findings of these experiments and inform on rational design strategies. Qualitatively, the theory agrees with our simulations and reproduces the salient experimental features. We also provide a set of testable predictions: the aspect ratio of the nematogens, their initial orientational order when cross-linked into the polymer network and the cross-linking fraction of the network all increase the plasticization time required for the film to macroscopically deform. We demonstrate that the dynamic response to oscillating electric fields is characterized by two resonances, which can likewise be influenced by varying these parameters, providing an experimental handle to fine-tune device design

The Rascal meta-programming language - a lab for software analysis, transformation, generation & visualization

National audienceThis paper summarizes the goals and features of a do- main specific programming language called Rascal. On the one hand it is designed to facilitate software research -- research about software in general. On the other hand Rascal is applied to specific software portfolios as well, as a means to improve them and as a means to learn to understand them. Specifically, Rascal is used create tools that analyze, transform, generate or visualize source code of software products. Such tools are motivated by the need to im- prove quality of existing software or the need to lower its cost-of-ownership. More generally such tools are cre- ated to build laboratory experiments that observe and measure quality, or try and improve software quality, etc. In this paper we provide an overview of Rascal as a "domain specific language for meta programming". We first explain its goals and then its features. We end by highlighting some example applications in the area of software analysis and transformation

A10 – Human Factors Considerations of UAS Procedures and Control Stations: Tasks PC-1 through PC-3 Pilot and Crew (PC) Subtask, Recommended Requirements and Operational Procedures

The Alliance for System Safety of UAS through Research Excellence (ASSURE) conducted research focused on minimum pilot procedures and operational practices used by unmanned aircraft systems (UAS) operators today for the purpose of developing recommendations. This research recommends four pilot and 46 operational minimum procedures to operate a civil single-engine, fixed-wing, single-pilot-configured UAS flying in beyond visual line-of-sight (BVLOS) conditions. These recommendations are anticipated to support potential future aircrew procedure requirements for UAS larger than 55 lbs. operating in the National Airspace System (NAS). These procedures were validated using representative Control Stations in simulated environments

Determining the electronic performance limitations in top-down fabricated Si nanowires with mean widths down to 4 nm

Silicon nanowires have been patterned with mean widths down to 4 nm using top-down lithography and dry etching. Performance-limiting scattering processes have been measured directly which provide new insight into the electronic conduction mechanisms within the nanowires. Results demonstrate a transition from 3-dimensional (3D) to 2D and then 1D as the nanowire mean widths are reduced from 12 to 4 nm. The importance of high quality surface passivation is demonstrated by a lack of significant donor deactivation, resulting in neutral impurity scattering ultimately limiting the electronic performance. The results indicate the important parameters requiring optimization when fabricating nanowires with atomic dimensions

Preclinical quality, safety, and efficacy of a human embryonic stem cell-derived product for the treatment of Parkinson’s disease, STEM-PD

Cell replacement therapies for Parkinson’s disease (PD) based on transplantation of pluripotent stem cell-derived dopaminergic neurons are now entering clinical trials. Here, we present quality, safety, and efficacy data supporting the first-in-human STEM-PD phase I/IIa clinical trial along with the trial design. The STEM-PD product was manufactured under GMP and quality tested in vitro and in vivo to meet regulatory requirements. Importantly, no adverse effects were observed upon testing of the product in a 39-week rat GLP safety study for toxicity, tumorigenicity, and biodistribution, and a non-GLP efficacy study confirmed that the transplanted cells mediated full functional recovery in a pre-clinical rat model of PD. We further observed highly comparable efficacy results between two different GMP batches, verifying that the product can be serially manufactured. A fully in vivo-tested batch of STEM-PD is now being used in a clinical trial of 8 patients with moderate PD, initiated in 2022