Open source software (OSS)-based product development takes advantage of feature updates and bug fixes from OSS communities. However, when we customize the OSS and do not return the changes back to the OSS communities, our customization and the updates sometimes conflict. That makes it difficult to apply forthcoming OSS updates since we need to grasp the software changes appropriately. We propose a method to visualize software's structural differences using call graph. We have applied the method to a product development process and found that our method helps developers to speed up the application of OSS updates and reduce update errors. We have also found that solely providing call graph is insufficient for them to check the differences. They need more detailed information, e.g. data flow, as well as a guide to utilize the difference information to resolve the conflicts.

In this paper, we propose a ubiquitous augmented reality system that expands projected augmentations in wide area by using visible light communication and wireless tag. The system consists of wireless tags and a high-speed projector (DMD Discovery 3000), operating in 8kHz, attached on mobility platform. The projector transmits structured light patterns that contain different information in each pixel. Wireless tags can recognize their own locations in projected area by receiving structured light patterns projected from the projector. Since 3D coordinates of individual tag is stored in the system, projection point is estimated with 3D coordinates and pixel coordinates of each tag in projected area. According to the estimated position and orientation, augmented reality content is superimposed. The set of structured light patterns are projected in sufficient speed that human eye can only perceive the superimposed content. We have also evaluated the accuracy of superimposing augmented reality content on real world from moving projection points.