Abstract
In this paper, we analyze environmental regulation based on tradable emission permits in the presence of strategic interaction in an output market with differentiated products. We characterize firms' equilibrium behavior in the permits and in the output market and we show that both firms adopt "rival's cost-rising strategies". Then, we study the problem of the regulator that aims at maximizing social welfare, proposing an efficient criterion to allocate permits between firms. We find that the optimal allocation criterion requires a perfect balance between the difference on firms' price-cost margins in the permits market and the difference on firms' mark ups in the output market. In light of the previous result, we use a simulation to obtain the optimal allocation of permits between firms as a function of output market characteristics, in particular as a function of goods substitutability. © 2012 World Scientific Publishing Company.

Abstract
In this paper we present three hybrid heuristics for the single machine scheduling problem with quadratic earliness and tardiness costs, and no machine idle time. Our heuristic is a combination of a steady-state genetic algorithm and three improvement procedures. The two computationally less expensive of these three improvement procedures are used inside the genetic algorithm to improve the schedule obtained after the application of genetic operators, whereas the more expensive one is used to improve the best solution returned by the genetic algorithm. We have compared our hybrid approaches against existing recovering beam search and genetic algorithms. The computational results show the effectiveness of our hybrid approaches. Indeed, our hybrid approaches outperformed the existing heuristics in terms of solution quality as well as running time.

Abstract

Abstract
In this work, two all-fiber interferometric configurations based on suspended core fibers (SCF) are investigated. A Fabry-Perot cavity (FPC) made of SCF spliced in-between segments of single-mode and hollow-core fiber is proposed. The interferometric signals are generated by the refractive-index mismatches between the two fibers in the splice region and at the end of the suspended-core fiber. An alternative sensing head configuration formed by the insertion of a length of SCF as a birefringence element in a Sagnac loop interferometer is also demonstrated. In this structure, the interferometric signals are generated by interfering two counter propagating beams with different polarization states which propagate through a length of SCF as a birefringence element. The sensitivity to pressure and temperature was determined for both configurations. The results show that the pressure sensitivities are -4.68 x 10(-5) nm/psi and 0.032 nm/psi for FPC and Sagnac loop interferometers, respectively. The temperature sensitivity of both structures has been obtained and the results have been discussed.

Abstract
Notable Byzantine Fault Tolerant protocols have been designed so far. These protocols are often evaluated on simple benchmarks, and few times on NFS systems. On the contrary, studies that addressed the behavior of BFT on large back-ends, like Directories, are few. We believe that studying such systems is crucial for practice community due to their popularity. In this paper, we integrate BFT with OpenLDAP Directory. We introduce the design of the integrated system, that we call BFT-LDAP. Then, we study its behavior accompanied with some useful observations. In addition, we discuss the cost overhead of this integration. Our approach ensures that OpenLDAP legacy code remains completely intact, and that the integration with BFT is straightforward using APIs. Moreover, we convey that the additional performance cost of BFT-LDAP is negligible as compared to that of stand-alone OpenLDAP. We conducted our experiments on Emulab. The experiments indicate that the performance discrepancy of BFT-LDAP is negligible whenever different state-of-the-art BFT protocols are used. Other experiments demonstrate that a little sacrifice in throughput (less than 10%) is needed in order to leverage the resiliency of OpenLDAP against Byzantine faults (i.e., through applying BFT). © 2012 IEEE.

Abstract
The aim of this paper is to present an adaptation model for an Adaptive Educational Hypermedia System, PCMAT. The adaptation of the application is based on progressive self-assessment (exercises, tasks, and so on) and applies the constructivist learning theory and the learning styles theory. Our objective is the creation of a better, more adequate adaptation model that takes into account the complexities of different users.