Abstract-The Deletion-Insertion Correcting Code construction proposed by Davey and MacKay consists of an inner code that recovers synchronization and an outer code that provides substitution error protection. The inner code uses low-weight codewords which are added (modulo two) to a pilot sequence. The receiver is able to synchronise on the pilot sequence in spite of the changes introduced by the added codeword.The original bit-level formulation of the inner decoder assumes that all bits in the sparse codebook are identically and independently distributed. Not only is this assumption inaccurate, but it also prevents the use of soft a-priori input to the decoder. We propose an alternative symbol-level inner decoding algorithm that takes the actual codebook into account. Simulation results show that the proposed algorithm has an improved performance with only a small penalty in complexity, and it allows other improvements using inner codes with larger minimum distance.

For many years, NTNU in Ålesund (formerly Aalesund University College) has maintained a close relationship with the maritime industrial cluster, centred in the surrounding geographical region, thus acting as a hub for both education, research, and innovation. Of many common relevant research topics, virtual prototyping is currently one of the most important. In this paper, we describe our first complete version of a generic and modular software framework for intelligent computer-automated product design. We present our framework in the context of design of offshore cranes, with easy extensions to other products, be it maritime or not. Funded by the Research Council of Norway and its Programme for Regional R&D and Innovation (VRI), the work we present has been part of two separate but related research projects (grant nos. 241238 and 249171) in close cooperation with two local maritime industrial partners.We have implemented several software modules that together constitute the framework, of which the most important are a server-side crane prototyping tool (CPT), a client-side web graphical user interface (GUI), and a client-side artificial intelligence for product optimisation (AIPO) module that uses a genetic algorithm (GA) library for optimising design parameters to achieve a crane design with desired performance. Communication between clients and server is achieved by means of the HTTP and WebSocket protocols and JSON as the data format.To demonstrate the feasibility of the fully functioning complete system, we present a case study where our computer-automated design was able to improve the existing design of a real and delivered 50-tonnes, 2.9 million EUR knuckleboom crane with respect to some chosen desired design criteria.Our framework being generic and modular, both clientside and server-side modules can easily be extended or

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Digital fingerprinting has been suggested for copyright protection. Using a watermarking scheme, a fingerprint identifying the buyer is embedded in every copy sold. If an illegal copy appears, it can be traced back to the guilty user. By using collusion-secure codes, the fingerprinting system is made secure against cut-and-paste attacks. In this paper we study the interface between the collusion-secure fingerprinting codes and the underlying watermarking scheme, and we construct several codes which are both error-correcting and collusion-secure. Error-correction makes the system robust against successful attacks on the watermarking layer.

Abstract-Digital fingerprinting is a forensic method against illegal copying. The distributor marks each individual copy with a unique fingerprint. If an illegal copy appears, it can be traced back to one or more guilty pirates due to this fingerprint. To work against a coalition of several pirates, the fingerprinting scheme must be based on a collusion-secure code. This paper addresses binary collusion-secure codes in the setting of Boneh and Shaw (1995/1998). We prove that the Boneh-Shaw scheme is more efficient than originally proven, and we propose adaptations to further improve the scheme. We also point out some differences between our model and others in the literature.