Accurate 3D maps from depth images and motion sensors via nonlinear Kalman filtering

This paper investigates the use of depth images as localisation sensors for 3D map building. The localisation information is derived from the 3D data thanks to the ICP (Iterative Closest Point) algorithm. The covariance of the ICP, and thus of the localization error, is analysed, and described by a Fisher Information Matrix. It is advocated this error can be much reduced if the data is fused with measurements from other motion sensors, or even with prior knowledge on the motion. The data fusion is performed by a recently introduced specific extended Kalman filter, the so-called Invariant EKF, and is directly based on the estimated covariance of the ICP. The resulting filter is very natural, and is proved to possess strong properties. Experiments with a Kinect sensor and a three-axis gyroscope prove clear improvement in the accuracy of the localization, and thus in the accuracy of the built 3D map.Comment: Submitted to IROS 2012. 8 page

Being Small and Managing Communities : An explorative study on how SMEs utilize community management to communicate

Research on community management conducted in the past has used primarily examples and case studies within large corporations. Small and medium sized enterprises (SMEs) also need to be included in community management, exploring the ways in which they deal with community management and if the large company theories on the subject can be applied to them. In an attempt to respond to this gap in community management we respond to the question of how do small and medium-sized companies utilize communities to communicate successfully to their consumers? During our work, we noted that SMEs were facing two phases when dealing with community management. A strategic step, where the company has to define its goals, its targets, the means it will invest and the tools it will use to deal with community management. The second phase being an operational step includes the creation of communities and the management of them. In the strategic step, we pointed out questions which companies have to address before starting community management including the benefits that the company expects from the community, the amount it will invest in it and the tools the company will use. In the operational step, five main principles were highlighted as commonly used by SMEs to communicate through communities: (1) promotion of an Ideal, (2) uniting around shared interests, (3) the use of the myth as a gathering factor, (4) the importance of the community involvement in the company, and (5) the physical interaction between community members and the brand. Additionally, we found that SMEs have two main advantages when it comes to collaborating with customers/fans that large businesses did not have: proximity and flexibility. However, we found that it was difficult for small companies to find competent people working in the community management field. This lack of knowledge within SMEs appeared to be the primary reason why most brand communities failed. Therefore, in this thesis we aimed to point out good habits in terms of community management in order for SMEs to possess a basic knowledge, thus enabling them to benefit from their advantages of proximity and flexibility, which are a result of by their size and is essential for community management

Validation of Final Examination in Danish as a Foreign Language for Secondary School Students in Latvia

Šajā maģistra darbā tiek aplūkotas galvenās valodu pārbaudīšanas un pārbaudes darbu izveides problēmas. Pētījuma ietvaros tika izveidots noslēguma sasniegumu pārbaudes darbs dāņu valodā, pamatojoties uz VISC centralizēto eksāmenu norādījumiem. Tika veikta pārbaudes darba validācija, izmantojot dažādas metodes. Darba mērķis ir izpētīt galvenos aspektus valodu pārbaudīšanā un pārbaudes darbu izveidē un pārbaudīt to praksē. Maģistra darba teorētiskā daļa tiek koncentrēta uz valodu pārbaudīšanu, galvenajiem kritērijiem pārbaudīšanā un pārbaudes darbu izveides procesā. Praktiskajā daļā tika izveidots noslēguma pārbaudes darbs dāņu valodā vidusskolas pēdējās klases skolēniem, kurš tika izmantots praksē un tika veikts kvalitatīvs pētījums par pārbaudes darbu un tā rezultātiem, kā arī tika veikta šī pētījuma rezultātā iegūtās informācijas analīze. Pētījuma rezultāti rāda, ka pārbaudes darbu izveides procesā ir svarīgi atlasīt derīgas sastāvdaļas, kas būtu atbilstošas paredzamajam pārbaudāmo valodas līmenim. Lai izvairītos no kļūdainām sastāvdaļām, ir nepieciešama pārbaudes darba vairākkārtēja pārskatīšana. Ja visi kritēriji tiek ievēroti, pārbaudes darbs ir uzticams un derīgs.The present Master Thesis looks at the main issues in language testing and test development. Under the research a final achievement test in Danish was developed according to the guidelines of VISC, and validation of it was carried out by implementing different methods. The purpose of the thesis is to research the main issues in language testing and test development and apply them into practice. The theoretical part of the thesis is focused on language testing, the main considerations in testing and the process of test development. During the practical part of the thesis a final Danish test for secondary school graduate students was developed, implemented in practice and qualitative research on the test and its results was carried out; analysis of the information obtained in the research was carried out. The results of the research show that it is important to select the items, which respond to the expected language level of the testees, of test carefully. In order to avoid faulty items, revision is necessary during test development. If all the criteria are observed, the test is reliable and valid