Swedish Institute of Computer Science Publications Database
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Scalable Visual Codes for Embedding Digital Data in the Physical World
No full textVisual codes, such as QR codes, offer a low-cost alternative to RF technology when digital data needs to be embedded in objects in the physical world. However, in order to sup- port receivers with a poor visual channel, e.g. low-resolution cameras, most visual codes are designed for low data capacity and short reading distances.
We present our work-in-progress on Focus, a visual code that avoids earlier work’s explicit trade-off between code capacity and channel quality. Rather than encoding the pay- load directly into individual pixels, Focus encodes the pay- load over a range of spatial frequencies. As a result, even a receiver with a very poor channel (e.g., with low-resolution camera or motion blur) can still partly decode a Focus code, because the code’s low-frequency components are robust to common channel impairments. A receiver with a good channel can decode all data from the same code.
In our demo, we will present a prototype of Focus for smartphones and showcase how it deals with common impairments of the visual channel
NetInf Live Video Specification
No full textThis document specifies how the NetInf information-centric network service can be used for transport of live video streaming. To illustrate this it describes a prototype system that was developed to be used at "events with large crowds", e.g., sports events. The specification defines how the used video format is mapped to NetInf named data objects (NDOs). It also describe how NetInf messages are used to transfer the NDOs
CODE – slutrapport
No full textTo get the right competence at the right time can often be crucial for a company. This competence can be of different types, e.g. data from a system or human knowledge related to a specific problem. The idea with CODE (Competence On DEmand) is to support the process industry by finding models and system which through new technology (like augmented and virtual reality) can facilitate the recruitment and supply of specialists, bridge generation gap and increase quality assurance in the transfer of knowledge between employees – to make sure the right competence is available when it is needed. This project has examined two companies with different prerequisites to see if modern technology could help them with their competence needs.
ABB FACTS runs operations in many parts of the world and it can be complicated to coordinate maintenance actions for all the different sites. Instead of sending specialists to support the different operations (which cost money and is very time inefficient) could it be possible to use some kind of remote guidance solution instead?
For Gyproc, a big plaster manufacturer, quality insurance is of the essence and it is crucial that different persons interpret information in the same way. Could augmented reality be used to make it easier for the operators to access information and could virtual reality be used to better prepare the operators before their shift begin?
The results of this study show that a remote guidance system using augmented reality could really facilitate the process of helping a technician working remotely. It is also possible to construct a virtual environment where operators could learn how to perform difficult tasks and procedures in a safe way.
In this project the main question was “is it possible to use modern technology to solve the problems these companies have”? The answer was yes so now the next step is a new project where the findings in CODE are used to create a prototype of a system that solves these problems
Quality assurance in software ecosystems: A systematic literature mapping and research agenda
No full textAbstract Software ecosystems are becoming a common model for software development in which different actors cooperate around a shared platform. However, it is not clear what the implications are on software quality when moving from a traditional approach to an ecosystem, and this is becoming increasingly important as ecosystems emerge in critical domains such as embedded applications. Therefore, this paper investigates the challenges related to quality assurance in software ecosystems, and identifies what approaches have been proposed in the literature. The research method used is a systematic literature mapping, which however only resulted in a small set of six papers. The literature findings are complemented with a constructive approach where areas are identified that merit further research, resulting in a set of research topics that form a research agenda for quality assurance in software ecosystems. The agenda spans the entire system life-cycle, and focuses on challenges particular to an ecosystem setting, which are mainly the results of the interactions across organizational borders, and the dynamic system integration being controlled by the users
Methods, Nodes and system for enabling redistribution of cell load
No full textPatent for distributed load balancing mechanism for LTE, developed by SICS in collaboration with Ericsson DUR
Integrating non-parametric models with linear components for producing software cost estimations
No full textA long-lasting endeavor in the area of software project management is minimizing the risks caused by under- or over-estimations of the overall effort required to build new software systems. Deciding which method to use for achieving accurate cost estimations among the many methods proposed in the relevant literature is a significant issue for project managers. This paper investigates whether it is possible to improve the accuracy of estimations produced by popular non-parametric techniques by coupling them with a linear component, thus producing a new set of techniques called semi-parametric models (SPMs). The non-parametric models examined in this work include estimation by analogy (EbA), artificial neural networks (ANN), support vector machines (SVM) and locally weighted regression (LOESS). Our experimentation shows that the estimation ability of SPMs is superior to their non-parametric counterparts, especially in cases where both a linear and non-linear relationship exists between software effort and the related cost drivers. The proposed approach is empirically validated through a statistical framework which uses multiple comparisons to rank and cluster the models examined in non-overlapping groups performing significantly different
Kapacitetsutnyttjande på järnvägen år 2030
No full textI denna rapport estimeras den belastning som kan uppstå på Sveriges järnvägssystem år 2030 om tillväxten för godstransporter blir som prognoser förutspår. Hänsyn har tagits till de kända planerade utbyggnaderna av infrastrukturen. Resultaten visar att det på delar av nätet kommer att bli mycket hög belastning – högre belastning än vad som idag anses hanterbart. Det gäller speciellt Södra Stambanan. På Västra Stambanan och den enkelspåriga delen av Godsstråket genom Bergslagen nås också ett mycket högt belastningsläge.
Passagerartrafiken har i denna studie antagits vara konstant, dvs passagerartrafiken 2030 antas ha samma omfattning som 2010. Detta gör att skattningen av belastningen kan betraktas som konservativ, eftersom även persontrafiken förutspås att öka fram till 2030.
Rapporten är slutrapport från projekt ”KLIPS – Klimat på spåret”
Localization using Anonymous Measurements
No full textRange-based IEEE 802.15.4 localization systems currently require relatively high anchor density for indoor deployments. It can therefore be beneficial to use external sources of transmission as additional anchors. We present methods for using WiFi beacons to improve localization accuracy of a range-based IEEE 802.15.4 localization system in cases where only two IEEE 802.15.4 anchor nodes are available. We do this by identifying WiFi beacons from RSSI traces that we dynamically sample online, and applying fingerprinting and range-based methods using the RSSI values of the identified beacons. However, because the data of the WiFi traffic is not decodable by the IEEE 802.15.4 devices, these RSSI measurements lack identifiers that can associate them to specific WiFi Access Points (APs). Therefore, novel methods are required for both fingerprinting and range-based approaches to allow for these additional WiFi APs to be used as anchors. We show by using real-world measurements that our beacon identification method gives a false-positive rate of only 3%, and that if the range measurements to the IEEE 802.15.4 anchors are relatively accurate, with a standard deviation of 1
and 3 m, a localization accuracy improvement of 47% and 24% can be gained, respectively
Multi-Criteria Test Case Prioritization Using Fuzzy Analytic Hierarchy Process
No full textOne of the key challenges in software testing today is prioritizing and evaluating test cases. The decision of which test cases to design, select and execute first is of great importance, in particular considering that testing is often done late in the implementation process, and therefore needs to be done within tight resource constraints on time and budget. In practice, prioritized selection of test cases requires the evaluation of different test case criteria, and therefore, test case prioritization can be formulated as a multi-criteria decision making problem. As the number of decision criteria grows, application of a systematic decision making solution becomes a necessity. In this paper we propose an approach for prioritized selection of test cases by using the Analytic Hierarchy Process (AHP) technique. To improve the practicality of the approach in real world scenarios, we apply AHP in fuzzy environment so that criteria values can be specified using fuzzy variables than requiring precise quantified values. One of the advantages of the decision making process it that the defined criteria with the biggest and most critical role in priority ranking of test cases is identified. We have applied our approach on an example case in which several test cases for testing non-functional requirements in a systems are defined