Abstract-In this paper, we present an unsupervised technique to segment and detect objects in indoor environments. The main idea of this work is to identify object instances whenever there is evidence for at least one other occurence of an object of the same kind. In contrast to former approaches, we do not assume any given segmentation of the data, but instead estimate the segmentation and the existence of object instances concurrently. We apply graph-based clustering in feature and in geometric space to presegmented input data. Each segment is treated as a potential object part, and the inter-dependence of object labels assigned to part clusters are modeled using a Conditional Random Field (CRF) named the "parts graph". Another CRF is then applied to the scene graph to smooth the class labels using the distributions obtained from the parts graph. First results on indoor 3D laser range data are evaluated and presented.

We implemented single-session workshops using the Thymio-II-a small, self-contained robot designed for young students, and VPL-a graphical software development environment based upon event handling. Our goal was to investigate if the students could learn this core computer science concept while enjoying themselves in the robotics context. A visual questionnaire was developed based upon the combined Bloom and SOLO taxonomies, although it proved difficult to construct a questionnaire appropriate for young students. We found that-despite the short duration of the workshop-all but the youngest students achieved the cognitive level of Unistructural Understanding, while some students achieved higher levels of Unistructural Applying and Multistructural Understanding and Applying.

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An acidic polysaccharide CS-F2 from Camellia sinensis was examined to characterize its anti-adhesive effects against pathogenic bacteria, most notably Helicobacter pylori, Propionibacterium acnes, and Staphylococcus aureus. CS-F2 showed marked inhibitory activity against the pathogen-mediated hemagglutination with a minimum inhibitory concentration (MIC) between 0.01 and 0.1 mg/mL, which is lower than the previously reported MIC values for Panax ginseng and Artemisia capillaris. The inhibitory effects of CS-F2 on the adhesion of H. pylori to AGS adenocarcinoma gastric epithelial cells, or P. acnes and S. aureus to NIH 3T3 fibroblast cells, were further assessed resulting in MIC values between 0.063 and 0.13 mg/mL. Importantly, CS-F2 showed no inhibitory effects against Lactobacillus acidophilus, Escherichia coli, or Staphylococcus epidermidis. Our results suggest that CS-F2, which is a pectin-type polysaccharide with a molecular weight of approximately 8.0 x 10(4) Da, may exert a selective anti-adhesive effect against certain pathogenic bacteria, while exerting no effects against beneficial and commensal bacteria.

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