Allen Y. Chang

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Cloud computing has become one of the most significant issues in recent years. Those associative applications and services based on cloud computing are dramatically emerging. However, in order to enjoy the widely utilization of cloud computing through wired/wireless networking, providing sufficient assurance of information security such as confidentiality,(More)
In circuit simulation, Relaxation-based algorithms have been proven to be faster and more flexible than the standard direct approach used in SPICE. ITA (Iterated Timing Analysis) algorithm has even been widely used in industry. This paper describes accelerating techniques that enable ITA to utilize circuits' multi-rate behaviors. These techniques are based(More)
Statistics from various sources indicate that there are roughly 75% cyber attacks occurred in the web applications, and the trend is growing. The unsafe coding of web application or the vulnerability of the application itself is yet to be patched result in a high security risk. In addition to white-box testing to examine the source code, black box testing(More)
The <i>ray shooting</i> problem arises in many different contexts. For example, solving it efficiently would remove a bottleneck when images are ray-traced in computer graphics. Unfortunately, theoretical solutions to the problem are not very practical, while practical solutions offer few provable guarantees on performance. In particular, the running times(More)
In the past few years, social networking websites such as Facebook and Myspace become very popular. The usage rage of social networking websites even exceeds that of Google. Followed by the popularity is many potential networking threats. How to prevent and improve these threats to avoid their expansion has become a major challenge.
Due to rapid advance of the RFID systems, there is sufficient computing power to implement the encryption and decryption required for the authentication during transactions nowadays. In addition, RFID tags have enough capacity to store the corresponding information. Therefore, RFID enabled credit card can be used to improve the potential security issues(More)
Road formation is the basic requirement of modern country. Manholes on the road are the main objects result in uneven surfaces. They are not only the killer of public safety, but also the main cause of national compensation; therefore, it is necessary to implement the underground manhole. However, it is not easy to search for the manhole from underground.(More)
There are many difficulties for face recognition, such as varying illumination, facial expressions, high dimensions of images, and optimal classifier design. The facial features would be vague by varying illumination and the positions of facial features would be changed by expressions. These problems influence on the recognition results heavily. Moreover,(More)
This paper considers an alternative strategy to speed up the circuit simulation. This strategy considers characteristics of simulator users' behaviors and involves two techniques, the incremental simulation and simulation-on-demand (SOD). These techniques are implemented in an "Interactive Simulation Environment" to dramatically accelerate the simulation(More)
In circuit simulation, Relaxation-based algorithms have been proven to be faster and more flexible than the standard direct approach used in SPICE. ITA (Iterated Timing Analysis) algorithm has even been widely used in industry. This paper describes a new accelerating technique using the latency property of subcircuits and other accelerating methods based on(More)