An experimental analysis of hydrogen enrichment on combustion characteristics of a gasoline Wankel engine at full load and lean burn regime

In this paper, a gasoline Wankel engine was modified and equipped with self-developed hybrid electronic control unit to experimentally investigate the effect of hydrogen-enrichment level on combustion characteristics of a gasoline Wankel engine at wild open throttle position and lean burn regime. Testing were carried out under constant engine speed of 3000 rpm and the lean operating limit of the original gasoline engine. The spark timing was set at 15 °BTDC. The hydrogen energy fraction in the intake was gradually increased from 0% to 10%. The results showed that hydrogen enrichment was effective on improving the combustion process through the shortened of the flame development and the flame propagation periods, advancing the central heat release, increasing the HRRmax and reducing the cyclic variation proportionally to the amount of hydrogen added to the air fuel mixture. Furthermore, increasing hydrogen fraction in the intake improves the engine economy by reducing the cooling loss.     

In-plane rotation analysis by two-wavelength electronic speckle interferometry

A simple method is presented for the measurement of in-plane rotation (angle and sign) of an object by use of the conventional in-plane sensitive electronic speckle pattern interferometry technique combined with the two-wavelength laser diode method. The advantage of this method is that it can be used to measure the angle of rotation in a simple way by determination of fringe tilt. The experimental setup is described, and results are presented.     

Towards a construction of an intelligent business process based on cloud services and driven by degree of similarity and QoS

Knowledge and competence management in companies focus on resources allocation to business activities, knowledge management approaches promise a positive impact on cost structures. Moreover, with cloud computing and multi-agent systems, we can have a positive impact on business process construction. In fact, cloud computing gives us the ability to perceive resources such as unlimited computer resources. Meanwhile, multi-agent systems provide some degree of independence to achieve specific goals. Nowadays, on the web we can find a significant number of services that provide the same functionality. Hence, business process construction by reusing these services has become a challenging problem. The solution proposed in this paper, can be considerate as an enterprise solution to construct a business process using some competence and knowledge management aspects. Furthermore, the solution is based on cloud computing and agents to discover similar services and classify services according to their similarity degrees and their quality of services.     

Observer-based Adaptive Fuzzy Backstepping Tracking Control of Quadrotor Unmanned Aerial Vehicle Powered by Li-ion Battery

In this paper, an Adaptive Fuzzy Backstepping Control (AFBC) approach with state observer is developed. This approach is used to overcome the problem of trajectory tracking for a Quadrotor Unmanned Aerial Vehicle (QUAV) under wind gust conditions and parametric uncertainties. An adaptive fuzzy controller is directly used to approximate an unknown nonlinear backstepping controller which is based on the exact model of the QUAV. Besides, a state observer is constructed to estimate the states. The stability analysis of the whole system is proved using Lyapunov direct method. Uniformly Ultimately Bounded (UUB) stability of all signals in the closed-loop system is ensured. The proposed control method guarantees the tracking of a desired trajectory, attenuates the effect of external disturbances such as wind gust, and solves the problem of unavailable states for measurement. Extended simulation studies are presented to highlight the efficiency of the proposed AFBC scheme.     

Robust Arabic speech recognition in noisy environments using prosodic features and formant

This paper investigates the contribution of formants and prosodic features such as pitch and energy in Arabic speech recognition under real-life conditions. Our speech recognition system based on Hidden Markov Models (HMMs) is implemented using the HTK Toolkit. The front-end of the system combines features based on conventional Mel-Frequency Cepstral Coefficient (MFFC), prosodic information and formants. The experiments are performed on the ARADIGIT corpus which is a database of Arabic spoken words. The obtained results show that the resulting multivariate feature vectors, in noisy environment, lead to a significant improvement, up to 27%, in word accuracy relative the word accuracy obtained from the state-of-the-art MFCC-based system.     

A flexible service selection for executing virtual services

With the adoption of a service-oriented paradigm on the Web, many software services are likely to fulfil similar functional needs for end-users. We propose to aggregate functionally equivalent software services within one single virtual service, that is, to associate a functionality, a graphical user interface (GUI), and a set of selection rules. When an end user invokes such a virtual service through its GUI to answer his/her functional need, the software service that best responds to the end-user’s selection policy is selected and executed and the result is then rendered to the end-user through the GUI of the virtual service. A key innovation in this paper is the flexibility of our proposed service selection policy. First, each selection policy can refer to heterogeneous parameters (e.g., service price, end-user location, and QoS). Second, additional parameters can be added to an existing or new policy with little investment. Third, the end users themselves define a selection policy to apply during the selection process, thanks to the GUI element added as part of the virtual service design. This approach was validated though the design, implementation, and testing of an end-to-end architecture, including the implementation of several virtual services and utilizing several software services available today on the Web.     

MRx as a participatory platform

Abstract

Facilitating and supporting various modes of social interaction has been part of Mixed Reality (MR^x)¹1 As defined in the introductory article for this series, MR^x experiences are conceptualized as site-specific; hybrid; and aesthetic, performative and/or social (For a detailed history of MR see, Introduction to this special issue) (Rouse et al., 2015b Rouse, R., Engberg, M., JafariNaimi, N., and Bolter, J. 2015b. “MR^x Design and Criticism: The Confluence of Media Studies, Performance, and Social Interaction.” Digital Creativity 26 (3/4). doi:10.1080/14626268.2015.1100124.[Crossref] , [Google Scholar]). design experiments and discourse over the past twenty years. But what vision of social interaction is sought and advanced through Mixed Reality environments? In this paper, I identify two dominant ways that social interaction is envisioned in MR^x designs, broadly construed as material and political, and illustrated through a series of examples. I further draw on them to highlight the potentials, boundaries, and limitations of each with regards to the kinds of social interactions that are sought and cultivated through the integration of digital media on physical space. I suggest that as MR becomes mainstream, it is important to go beyond these visions to consider whether and how MR^x environments might connect with the economic, social, and cultural specificity of local sites to meaningfully serve the always evolving social needs and purposes of their communities.     

Investigation of the Structural,Electronic and Mechanical Properties of Type-VIII Ba8Si46 Clathrate under High-Pressure through First-Principles

Silicon - By means of density functional theory (DFT) calculations, we have systematically investigated the effect of hydrostatic pressure on the structural, electronic and elastic properties of...     

Effects of sodium alginate coating containing Mentha spicata essential oil and cellulose nanoparticles on extending the shelf life of raw silver carp (Hypophthalmichthys molitrix) fillets

Food Science and Biotechnology - The aim of the present study was to evaluate the effects of sodium alginate (SA) coatings containing Mentha spicata essential oil (MSO; 0.5 and 1%) and cellulose...