41952008
Understanding User Preferences and Awareness: Privacy Mechanisms in Location-Based Services
Location based services (LBS) let people retrieve and share information related to their current position. Examples are Google Latitude or Panoramio. Since LBS share user-related content, location information etc., they put user privacy at risk. Literature has proposed various privacy mechanisms for LBS. However, it is unclear which mechanisms humans really find useful, and how they make use of them. We present a user study that addresses these issues. To obtain realistic results, we have implemented a geotagging application on the web and on GPS cellphones, and our study participants use this application in their daily lives. We test five privacy mechanisms that differ in the awareness, mental effort and degree of informedness required from the users. Among other findings, we have observed that in situations where a single simple mechanism does not meet all privacy needs, people want to use simple and sophisticated mechanisms in combination. Further, individuals are concerned about the privacy of others, even when they do not value privacy for themselves.
18116843
Service lifecycle management infrastructure for smart items
Smart items are physical objects that are enhanced by information technology. There are a number of different smart item technologies available, all of which have different capabilities, protocols, and management functionality. These devices have become an attractive solution for enterprise scenarios. In such scenarios lifecycle management can become a challenge when considering the differences of the smart item types while at the same time providing an abstraction for common functionality. We propose an infrastructure for service lifecycle management of smart items. It is part of a middleware called Smart Item Services Infrastructure (SI)2, which is able to provide a uniform access to various smart item types. The presented architecture addresses the platform heterogenity challenge with a separation of platform-specific and platform-independent functionality. Service Lifecycle Managers for the individual platforms translate the platform-independent requests into the device-specific protocol. Besides platform abstraction, the deployment planning of services is a major requirement. Thus, we put special focus on the Service Mapper component, which determines a deployment plan that satisfies a number of constraints.
16200249
Collaborative Smart Items
Business information systems provide computer support for decision making across huge data sets. Smart Items are miniaturized computer and sensing systems embedded into physical goods, items and assets. This paper proposes collaborative Smart Items for pushing business relevant computing as close as possible into the real world. Collaboration is enabled through an auction-based negotiation mechanism running distributed between the Smart Items. This mechanism serves as an abstraction across Smart Items in order to enable a common reasoning on business critical contexts as they may occur in logistics, safety and highly dynamic planning scenarios. In this paper, we investigate auction-based collaboration for Smart Items and present first experimental results. We conclude that auctions facilitate reliable business information processing even under harsh industrial conditions such as information loss or device failure.
13567817
Data Security in Service-Oriented Architectures
Due to standardized interfaces and loose coupling of services, serviceoriented architectures provide the possibility for close interaction between different organizations and communities. But this also introduces new risks: To have under control where which data is processed becomes increasingly difficult. This paper highlights that current approaches for ensuring data privacy and required security mechanisms are no longer adequate under these changing conditions and presents possible solutions discussed by researchers and developers. Additionally, economic implications of data privacy and security are considered.
135455031
Iterative Service Orchestration based on Dependability Attributes
In a service-oriented architecture (SOA), the orchestration of services to new services and complex workflows is a common approach. Because the complexity and capability of the orchestrated services are increased, it is important to maintain and ensure the dependability attributes, e.g. availability and reliability, in such an environment. Today, most approaches focus on the needs during the creation of a single application, but the Internet became a commodity for end users during the last years and more services are available every day. While the range of available services is growing, the end users are helpless selecting a service providing the quality of service they expect. Therefore, a straightforward approach is needed allowing the creation and modification of orchestrated services by end users with respect to dependability attributes.
11737906
A disk-based parallel implementation for direct condensation of large permutation modules
Through the use of a new disk-based method for enumerating very large orbits, condensation for orbits with tens of billions of elements can be performed. The algorithm is novel in that it offers efficient access to data using distributed disk-based data structures. This provides fast access to hundreds of gigabytes of data,which allows for computing without worrying about memory limitations.
 The new algorithm is demonstrated on one of the long-standing open problems in the Modular Atlas Project [11]: the Brauer tree of the principal 17-block the sporadic simple Fischer group Fi23 The tree is completed by computing three orbit counting matrices for the Fi23 orbit of size 11, 739, 046, 176 acting on vectors of dimension 728 over GF (2). The construction of these matrices requires 3-1/2 days on a cluster of 56 computers,and uses 8 GB of disk storage and 800 MB of memory per machine.
3419898
Gain in Transparency versus Investment in the EPC Network - Analysis and Results of a Discrete Event Simulation Based on a Case Study in the Fashion Industry
The diffusion rate of Radio Frequency Identification (RFID) technology in supply chains is lower than expected. The main reason is the doubtful Return On Investment (ROI) mainly due to high tag prices. In this contribution, we leverage a prototypical RFID implementation in the fashion industry, extend this prototype by a discrete event simulation, and discuss the impact of an Electronic Product Code (EPC)-enabled supply chain concerning higher visibility. Thereby, we illustrate the benefit of the EPC network for Supply Chain Event Management (SCEM). Future researchers are provided with the simulation data which is available online and can be investigated.
9329311
Intersection Line Length Normalization in CT Projection Data
We present a method to improve the quality of common sinogram restoration algorithms, which are used for metal-artifact reduction in X-ray CT. The presented approach is based on the idea that the intersection length of all beams through the object of interest can approximately be calculated from a preliminary reconstruction of the object. Incorporating this information to the reconstruction allows significant reduction of streak artifacts. Additionally, it is shown that the information about intersection length may also be used to improve the detection of metal shadows within the sinogram.