In recent years, point cloud data generated with RGB-D cameras, 3D lasers, and 3D LiDARs have been employed frequently in robotic applications. In indoor environments, RGB-D cameras, which have short-range and can only describe the vicinity of the robots, generally are opted due to their low cost. On the other hand, 3D lasers and LiDARs can capture long-range measurements and generally are used in outdoor applications. In this study, we deal with the segmentation of indoor planar surfaces such as wall, floor, and ceiling via point cloud data. The segmentation methods, which are situated in Point Cloud Library (PCL) were executed with 3D laser point cloud data. The experiments were conducted to evaluate the performance of these methods with the publicly available Fukuoka indoor laser dataset, which has point clouds with different noise levels. The test results were compared in terms of segmentation accuracy and the time elapsed for segmentation. Besides, the general characteristics of each method were discussed. In this way, we revealed the positive and negative aspects of these methods for researchers that plan to apply them to 3D laser point cloud data.

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Objective: Gastric intestinal metaplasia (GIM) is considered as a predisposing lesion for the development of gastric cancer and isrecommended to be kept under surveillance in designated intervals. We aimed to assess the natural course of GIM in a large Turkishcohort.Materials and Methods: We retrospectively reviewed findings from pathology reports of gastric biopsies conducted between 2011 to2018 to reveal patients diagnosed with solitary GIM in their index pathology report. Progression of GIM was pre-defined as; lowgradedysplasia (LGD), high-grade dysplasia (HGD), or gastric malignancy.Results: The median follow-up period of the study population was 34 (12-128) months. Out of 109 patients with GIM at the entry, 54(49.6%) patients had stable GIM, whereas 53 (48.6%) cases had no signs of GIM at their final endoscopy. Only two (1.8%) patientsprogressed to LGD, but no HGD or malignancy was detected in the follow-up.Conclusion: Although, considered as a premalignant lesion and offered surveillance globally, progression of GIM was very low in alarge Turkish cohort. Further prospective studies in larger cohorts are required to enlighten the obscure strategies in the surveillanceof gastric malignancy.