Ralf Jung

Iris: Monoids and Invariants as an Orthogonal Basis for Concurrent Reasoning

We present Iris, a concurrent separation logic with a simple premise: monoids and invariants are all you need. Partial commutative monoids enable us to express---and invariants enable us to enforce---user-defined *protocols* on shared state, which are at the conceptual core of most recent program logics for concurrency. Furthermore, through a novel extension of the concept of a *view shift*, Iris supports the encoding of *logically atomic specifications*, i.e., Hoare-style specs that permit the client of an operation to treat the operation essentially as if it were atomic, even if it is not.

guitAR: supporting guitar learning through mobile projection

The guitar is one of the most widespread instruments amongst autodidacts, but even though a huge amount of learning material exists, it is still hard to learn especially without a guitar teacher. In this paper we propose an Augmented Reality application called guitAR that assists guitar students mastering their instrument using a projector phone. With the projector phone mounted at the headstock of the guitar, the fret board and the strings of the guitar are in the field of projection of the phone. By projecting instructions directly onto the strings of the guitar the user is easily able to realize where the fingers have to be placed on the fretboard (fingering) to play a certain chord or a tone sequence correctly.

RustBelt: securing the foundations of the rust programming language

Rust is a new systems programming language that promises to overcome the seemingly fundamental tradeoff between high-level safety guarantees and low-level control over resource management. Unfortunately, none of Rusts safety claims have been formally proven, and there is good reason to question whether they actually hold. Specifically, Rust employs a strong, ownership-based type system, but then extends the expressive power of this core type system through libraries that internally use unsafe features. In this paper, we give the first formal (and machine-checked) safety proof for a language representing a realistic subset of Rust. Our proof is extensible in the sense that, for each new Rust library that uses unsafe features, we can say what verification condition it must satisfy in order for it to be deemed a safe extension to the language. We have carried out this verification for some of the most important libraries that are used throughout the Rust ecosystem.

Innovative Retail Laboratory - Investigating Future Shopping Technologies Innovative Retail Laboratory - Erforschung von Technologien für das Einkaufen von morgen

Abstract The Innovative Retail Laboratory (IRL) is an application-oriented research laboratory of the German Research Center for Artificial Intelligence (DFKI) run in collaboration with the German retailer GLOBUS SB-Warenhaus Holding in St. Wendel. In this living lab, we conduct research in a wide range of different domains all connected to intelligent shopping consultants, which range from a virtual assistant responsible for matters of dieting and allergies, over a digital sommelier, to personalized cross and up selling, smart items with digital product memories as a further development of the RFID technology, indoor positioning and navigation as well as new logistics concepts, to see if they are suitable for everyday life and useful for customers. New ways of customer interaction are developed and tested for implementation. The range varies from personalized shopping assistants to “talking” products and intelligent shopping carts, which plan and show the way through the store according to your shopping list. Furthermore they can give advice on what to buy for the recipes you have in mind, they compare products, point out special offers in a personalized way and give additional information about the products. However, the concepts and technologies that regard the self-service store of the future as a place for shopping are not IRL´s only focus. The relation between the store and its customers begins way before the shopping trip itself takes place. It starts with an individual shopping preparation and a personalized presentation of offers at home and will be continued afterwards through advice that is given about purchased goods and information about their use.

Using mobile projection to support guitar learning

The guitar is one of the most widespread instruments amongst autodidacts, but even though a huge amount of learning material exists, it is still hard to learn especially without a guitar teacher. In this paper we propose an Augmented Reality concept that assists guitar students mastering their instrument using a mobile projector. With the projector mounted onto the headstock of the guitar, it is possible to project instructions directly onto the strings of the guitar. With that the user is easily able to realize where the fingers have to be placed on the fretboard (fingering) to play a certain chord or a tone sequence correctly.

The Shopping Experience of Tomorrow: Human-Centered and Resource-Adaptive

What would the shopping experience of tomorrow look like? In this chapter we propose several human-centered and resource-adaptive ideas to this question. Throughout the whole chapter we explain our ideas with the recurrent theme of a shop that consists of instrumented shelves, public displays, audio systems, and mobile devices for each user.

Product-Awareness through Smart Audio Navigation in a Retail Environment

In this paper, we introduce a method to make personalized music freely selectable for each customer in a retail environment. Using a web interface, the customer can create an electronic shopping list, associate items with recommended music, and thus create his individual shopping play list. The provided instrumental music tracks are additionally categorized by their emotional expression to allow a selection based on the users favorite mood. The product-associated music tracks start playing at the customers instrumented shopping cart as soon as he enters specific product departments where items from his shopping list are located. We also introduce a service to provide product-awareness through non-speech audio cues. This location aware service notifies customers when they come closer to products that are listed on their shopping lists. We use a two stage notification approach by creating user-centric notification zones. Depending on the customers distance to the product, he gets notified by an ambient or arousal noise that is mixed into the background music. In doing so, customers become aware of products in their surrounding area that are listed on their personal shopping list.

Smart sound environments: merging intentional soundscapes, nonspeech audio cues and ambient intelligence

We introduce an intelligent audio notification system for multiuser environments that provides users with information about events (e.g., important emails) in a more discreet and non‐distracting way. The peripheral awareness of individual‐related events is done by using nonspeech audio cues which can be seamlessly integrated into artificial background soundscapes. These ambient soundscapes are self‐composed with respect to well‐known perceptual constraints such as auditive Gestalt laws as well as music psychological findings. To follow a hierarchical approach for the notification sounds we use notification instruments, ambient noises and traditional alert signals that are grouped by their level of intrusiveness. Since the notification system also follows a human‐centered approach it takes parameters like user preferences, his/her current position in the environment and the type of event into consideration to decide which notification is the appropriate at this time. In the paper, we will describe the architecture of the personalized ambient audio notification service, compositional constraints as well as some findings of a user study in which we tested successfully the efficiency of our system with 25 subjects.

A location-adaptive human-centered audio email notification service for multi-user environments

In this paper, we introduce an application for a discreet notification of mobile persons in a multi-user environment. In particular we use the current user position to provide a personalized email notification with non-speech audio cues embedded in aesthetic background music. The notification is done in a peripheral way to avoid distration of other people in the surrounding.

MoSeL: A General, Extensible Modal Framework for Interactive Proofs in Separation Logic

A number of tools have been developed for carrying out separation-logic proofs mechanically using an interactive proof assistant. One of the most advanced such tools is the Iris Proof Mode (IPM) fo...A number of tools have been developed for carrying out separation-logic proofs mechanically using an interactive proof assistant. One of the most advanced such tools is the Iris Proof Mode (IPM) for Coq, which offers a rich set of tactics for making separation-logic proofs look and feel like ordinary Coq proofs. However, IPM is tied to a particular separation logic (namely, Iris), thus limiting its applicability. In this paper, we propose MoSeL, a general and extensible Coq framework that brings the benefits of IPM to a much larger class of separation logics. Unlike IPM, MoSeL is applicable to both affine and linear separation logics (and combinations thereof), and provides generic tactics that can be easily extended to account for the bespoke connectives of the logics with which it is instantiated. To demonstrate the effectiveness of MoSeL, we have instantiated it to provide effective tactical support for interactive and semi-automated proofs in six very different separation logics.