METIS-II was an EU-FET MT project running from October 2004 to September 2007, which aimed at translating free text input without resorting to parallel corpora. The idea was to use “basic” linguistic tools and representations and to link them with patterns and statistics from the monolingual target-language corpus. The METIS-II project has four partners, translating from their “home” languages Greek, Dutch, German, and Spanish into English. The paper outlines the basic ideas of the project, their implementation, the resources used, and the results obtained. It also gives examples of how METIS-II has continued beyond its lifetime and the original scope of the project. On the basis of the results and experiences obtained, we believe that the approach is promising and offers the potential for development in various directions. 相似文献
A cyber-physical attack is a security breach in cyber space that impacts on the physical environment. The number and diversity of such attacks against Cyber-Physical Systems (CPSs) are increasing at impressive rates. In times of Industry 4.0 and Cyber-Physical Systems, providing security against cyber-physical attacks is a serious challenge which calls for cybersecurity risk assessment methods capable of investigating the tight interactions and interdependencies between the cyber and the physical components in such systems. However, existing risk assessment methods do not consider this specific characteristic of CPSs. In this paper, we propose a dependency-based, domain-agnostic cybersecurity risk assessment method that leverages a model of the CPS under study that captures dependencies among the system components. The proposed method identifies possible attack paths against critical components of a CPS by taking an attacker’s viewpoint and prioritizes these paths according to their risk to materialize, thus allowing the defenders to define efficient security controls. We illustrate the workings of the proposed method by applying it to a case study of a CPS in the energy domain, and we highlight the advantages that the proposed method offers when used to assess cybersecurity risks in CPSs.
Despite the fact that concrete is the most widely used construction material, conventional techniques for the estimation of the mechanical properties are only applicable to the hardened material. Moreover, concerning the fresh concrete examination, the already existing techniques provide only qualitative information, are not representative over the full time period of curing, setting and hardening or have limited accuracy and repeatability. In this study, the acoustic emission (AE) technique is employed in order to investigate the activity within fresh concrete as early as a few minutes after mixing. Several processes like settlement, segregation, formation and migration of air bubbles, as well as formation of hydrates produce AEs which so far have not been properly examined in literature. The first and foremost goal is to check the capacity of the new AE setup to record emissions earlier than previous studies (just after casting). The next goal concerns the possibility to characterize the different types of emissions relatively to their original source mechanism while the final goal would be the investigation of possible correlations between the early age acoustic activity and the final mechanical properties. For this reason, an AE setup is applied utilizing the favorable wave transmission properties of the metal casting molds, which act as a sort of waveguide. After validating its sensitivity, several laboratory tests are performed in concrete with varying water and aggregate content. It is found that the rate of AE activity follows trends similar to the typical hydration curves known from literature and is also indicative of the mix parameters. Finally, it should be mentioned that it is the first study that exploits the acoustic activity as early as the moment of mixing while apart from the number of emissions which is usually examined, the monitoring includes waveform parameters that show strong characterization potential. 相似文献
In this work the feasibility of Raman spectroscopy, especially the detection limit of this technique for the chemical characterization of multicomponent aerosols, which appear in technical processes has been investigated. In such kind of aerosols high number concentrations (>106 cm?3) can be observed whereas the range of the pollutant loading varies from 10–1000 mg/m3. For these purposes different type of aerosols have been investigated. Aerosols in which the pollutant can be found in the dispersed phase as well as in the gas phase (aqueous solutions of NH3 aerosols), those where the pollutant appears only in the dispersed phase (aqueous solutions containing SO42?/ NO3? salts) and aerosols where there is no Raman shift between the signals of the gas and the dispersed phase (toluene/ dodecane aerosols). Furthermore aerosols generated by the reaction between NH3 and HCl in nitrogen containing different amounts of vapor are also investigated. The characterization of the aerosols with Raman spectroscopy with respect to their gas phase is without any difficulty, whereas the analysis in the dispersed phase is partially marginal and in majority of cases almost not possible. Especially for the reaction aerosols rejection of elastically scattered light is the principle limitation in collecting Raman scattered light from particles in the Mie-scattering regime. 相似文献
Active noise control systems (ANCS) have been used extensively in several diverse applications in order to reduce the sound levels within a confined space. Several control schemes have been proposed, all of which rely on the same basic idea, namely that of introducing an artificial secondary sound field in order to partially cancel the primary sound field. This secondary field is created by using a number of actuators (usually speakers), placed in several locations within the space of interest. In our particular case of interest, the ANCS under consideration is an interior one. The overall ANCS comprises a set of sensors, a control system, and the actuators. Clearly, the optimal design of all three components needs to be addressed when designing an ANCS. In this paper, the problem of deciding to which specific locations (out of several possible ones) the actuators will be located for optimal performance of the ANCS is addressed. Specifically, a genetic algorithm is designed for this problem. The algorithm was implemented and tested against a simple greedy approach. Results indicate the efficiency of the Genetic Algorithm for the problem at hand. 相似文献
In this paper, the unified, abstract KEYSTONE Public Key Infrastructure is presented. This architecture consists of a reference model, a functional architecture specification, and a set of technologies that can be used for implementing the functional units, along with all relevant standards. It was derived within the course of the KEYSTONE project, which was funded by the European Commission under the Electronic Trust Services II Programme. The proposed PKI architecture guarantees openness, scalability, flexibility, extensibility, integration with existing TTP and information infrastructure, transparency and, above all, security. Thus, it enjoys all the desirable characteristics and fulfils all those criteria that are essential for a PKI to constitute a successful framework for the development of inter-domain and international Trusted Services. 相似文献
Optical control of the lateral quantum confinement and number of electrons confined in nanofabricated GaAs/AlGaAs quantum dots is achieved by illumination with a weak laser beam that is absorbed in the AlGaAs barrier. Precise tuning of energy-level structure and electron population is demonstrated by monitoring the low-lying transitions of the electrons from the lowest quantum-dot energy shells by resonant inelastic light scattering. These findings open the way to the manipulation of single electrons in these quantum dots without the need of external metallic gates. 相似文献