Web caching has been used extensively to enhance content delivery to the clients by minimizing ­client- ­observed latency, reducing network bandwidth usage and improving scalability of the network. Caching performance can be improved by designing good replacement policies, prefetching techniques, clustering of web users and proper placement of proxy caches in the network. In this paper, we discuss the various approaches that were designed based on neural networks, genetic algorithms and fuzzy logic to optimize the performance of web caching. The approaches discussed here proved to be more effective in solving the problems as compared to the conventional techniques that were used earlier in this problem domain. Neural networks and evolutionary algorithms can be considered for further exploration in the various issues related to web caching and content delivery.

Speaker recognition system may be viewed as working in four stages, namely, analysis, feature extraction, modeling and testing. This paper gives an overview of the major techniques developed in each of these stages. Such a review helps in understanding the developments that have taken place in each stage and also the available choices of techniques, along with their relative merits and demerits. A comparative study of different techniques is done at the end of each section to justify the choice of techniques available in the state-of-the-art speaker recognition systems. The paper is concluded with a discussion on the possible future direction for the development of techniques in each stage.

This paper presents fingerprint biometric-based self-authentication and deniable authentication schemes, which enable a receiver to identify source of the message but not to prove the identity of the sender to a third party. At first, we identify the security flaws of some recently proposed deniable authentication schemes by three application scenarios, and prove that those schemes are vulnerable to impersonation and eavesdropping attacks. For remedy, we propose two-factor-based self-authentication and deniable authentication schemes in which, firstly, each user has to perform self-authentication by something he knows (password) and something he is (biometrics), and then he can accomplish the transaction, e.g., e-commerce. Security analysis shows that the proposed schemes can overcome the security pitfalls of the previous schemes and are secure, reliable and practicable with high potential to be used in the electronic world.

In this paper, an innovative efficiency-boosting technique is successfully applied to typical linear light emitting diode (LED) drivers. Furthermore, p-channel MOSFET (PMOS) pass element with elaborate metal layout pattern is used to reduce dropout loss and a 5V regulated voltage is obtained from the wide range input voltage to power some sub-circuits. This will ­further diminish power dissipation and thus enhance efficiency. The proposed driver has been fabricated on a 0.5 µm Bipolar CMOS DMOS (BCD) process. process. Post-simulation results show that when driving three high brightness light emitting diodes (HB-LEDs) in series, it can achieve maximum efficiency of 91.12% at I _LOAD = 350 mA, which is improved by 7.3%, as compared with that of the typical one under the same condition. Besides, the proposed driver is able to operate with a wide input voltage range (6V~32V) and deliver output current up to 350 mA, with an accuracy of ±3%, regardless of process voltage temperature (PVT) variations. Besides, the dropout voltage is only 450mV when I _LOAD =350 mA and V _IN =12V.

Changes in equipment and production demand cannot be predicted at the design stage. Therefore, ­decision taking mechanisms must rely on real time information collected from the shop floor. To perform scheduling and routing optimization, not only modifications in values of parameters of interest, but also in the flow itself must be accounted for. This paper addresses this problem and proposes a method to formally model, at runtime, the flow within a service-oriented manufacturing line. The resulting representation assists ­deadlock- free dynamic scheduling of the system.

While many academic libraries are increasingly providing e­book services, a barrier to the adoption of e­books, however, is their unsatisfactory design. This paper reports on a study that investigates the students' preferences for the e­book designs, in an attempt to review what appeals to them in an ideal e­book. Comparison was made between three e­books in portable document format, all of which were non­fiction, but differed in contents and their styles of presentation. Based on the preliminary findings, some general guidelines were suggested for the improved design of e­books.