As technology for data storage and computing enhances on a new dimension, real world evidence based decision has become possible, and a new concept called "Big Data" has emerged. Leaders for Big Data technology development are mainly national security and medical field due to their urgent need of decision based on big data. Recent revelation of collection and analysis activities of National Security Agency (NSA) that cover massive data corresponding to the area of people's privacy triggered much controversy about concerns for infringing privacy and violation of constitutional rights. This, in turn, became opportunity of producing various analysis and opinions about the current level of big data technology, future possibility, types of work that big data has enabled, and technological and legal means for preventing expected abuse. The purposes of this paper are surveying materials about legal issues regarding NSA's activity with big data, and organizing feedbacks collected from various sources of the society.

With the rapid technological advances of the computer and the Internet, multimedia data is becoming increasingly widespread. People of all backgrounds are able to create, modify and distribute multimedia data around the world. Multimedia has essentially ushered in a new era of communication and information flow, which has had a significant impact on society. Creators have more opportunities to create content, specifically in the multimedia format. In addition, the intellectual property law plays a key role in protecting the value of multimedia works. However, in reality, it is not easy for the legal system to cope with changes regarding the format and content of multimedia works. In this paper we address the concept of multimedia, the role of copyright, and the technologies that can be used to protect the copyrights of multimedia work. We also discuss current issues on multimedia copyrights on the Web and present our suggestions to multimedia copyright protection on the Web.

Ray tracing naturally supports high-quality global illumination effects, but it is computationally costly. Traversal and intersection operations dominate the computation of ray tracing. To accelerate these two operations, we propose a hardware architecture integrating three novel approaches. First, we present an ordered depth-first layout and a traversal architecture using this layout to reduce the required memory bandwidth. Second, we propose a three-phase ray-triangle intersection architecture that takes advantage of early exit. Third, we propose a latency hiding architecture defined as the ray accumulation unit. Cycle-accurate simulation results indicate our architecture can achieve interactive distributed ray tracing.

We present an ordered depth-first tree layout for ray tracing. Among two child nodes, a child node with the larger surface area is stored next to its parent node. Hence, the probabilities that a ray accesses to the same cache line increase. Our approach can be easily and widely used for various ray tracing systems with very small overheads, as it is based on existing depth-first layouts.