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31.
Aerosol dispersion in living spaces especially bioaerosols, due to accidents or deliberate acts, is of significant current interest. Computational fluid dynamics (CFD) provides an accurate and detailed platform to study the influence of different parameters on aerosol distribution in indoor spaces. The simulations however are time consuming and site-specific. The work here introduces an approach toward addressing this challenge. During emergencies, an accurate, quicker, and more general model is required to give rapid answers to first responders. Significant parameters influencing aerosol behavior in an office room were identified and through dimensional analysis, nine dimensionless groups were developed. Fractional factorial design was used to build sixteen scenarios to explore the design space. These scenarios were then simulated using a comprehensive CFD model. Large eddy simulation with the Smagorinsky subgrid scale model was applied to compute the airflow. Aerosols were modeled as a dispersed solid phase using the Lagrangian treatment. The influence of the dimensionless groups on the temporal variation of the number of aerosols in the room and the spatial distribution of the particles in the room was analyzed. The results showed that all the identified dimensionless groups were significant. Multiple linear regression models were developed for the prediction of the number of aerosols in the room and their spatial distribution as a function of the significant parameters influencing aerosol transport. The linear models accurately predicted the data on which they were based but did not predict the results of the independent tests as well. The limited predictive ability of the model showed that the relationships between the dimensionless groups are nonlinear and a higher level of experimental design will have to be applied to better explore the design space. 相似文献
32.
Activity Awareness as an Enabler for Communication and Network Building in Construction Design Teams
Stefan Boddy Yacine Rezgui Grahame Cooper Matthew Wetherill 《Canadian Metallurgical Quarterly》2010,24(5):430-440
The paper reports on ongoing research into the facilitation of communication in distributed design teams of the type typically encountered in the construction sector. Ideas around social aspects in such design teams are discussed followed by our previous research efforts as an evolutionary process that has led us to develop in this direction. It is argued that facilitating timely and contextually grounded communication in a distributed environment can help to build the social networks and associated social capital common in collocated design teams but often absent in distributed ones. We describe our framework for providing such facilitation through monitoring and awareness of the information “space” of a construction project. We believe that by leveraging the relationships in the information space, we can go some way to identifying those individuals who would benefit from developing interpersonal relations in their work and further by exploiting those relationships in real time we can accelerate the formation of personal social networks and social capital between those individuals. 相似文献
33.
Jihene Rezgui Abdeltouab Belbekkouche Abdelhakim Hafid 《Mobile Networks and Applications》2011,16(1):122-133
Wireless Mesh Networks (WMN) have attracted increasing attention from the research community as a high-performance and low-cost
solution to last-mile broadband Internet access. On the other side, Optical Burst Switching (OBS) is a promising access technology
that uses optical fiber with burst switching paradigm. In this paper, we propose a novel Metropolitan Area Network (MAN) architecture,
called Optical Burst Wireless Mesh Architecture (OBWMA) which integrates WMN at the user access side and OBS at the core of the MAN. OBWMA aims to combine advantages of
both WMNs and OBS networks, such as large coverage at low cost and bandwidth availability. We specify the details of the interconnection
and the internetworking of WMNs and the OBS network in OBWMA. Moreover, we develop an analytical model to compute the end-to-end delay in OBWMA in order to support flow requests with delay constraints. Furthermore, we propose
a Control Bridge (CB) that ensures Quality of Service (QoS) mapping at the border between the WMN and the OBS parts. Also, we propose a burst
assembly scheme, called Adaptive Hybrid Burst Assembly scheme (AHBA). Simulation results using ns-2 demonstrate the feasibility of OBWMA and the validity of our analytical model. 相似文献
34.
Fathi Habashi Farouk T. Awadalla 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1986,36(1):1-6
When phosphate rock is dissolved in nitric acid, phosphoric acid and uranium can be selectively extracted by tertiary amyl alcohol; other impurities including the lanthanides remain in the aqueous phase. Uranium can be recovered from the alcohol phase by selective stripping and the lanthanides from the raffinate by extraction with tributyl phosphate. 相似文献
35.
DWT-based joint antenna selection for correlated MIMO channels 总被引:1,自引:0,他引:1
Ehab Farouk Badran 《Signal, Image and Video Processing》2009,3(1):35-45
This paper proposes a new discrete wavelet transform (DWT)-based joint antenna selection scheme for spatially correlated multiple-input
multiple output (MIMO) channels. To reduce the severe performance degradation of the traditional antenna selection schemes
in correlated channels, a new scheme which employ joint antenna selection (JAS) at both link ends algorithm and embed DWT
operations in the receiver-end RF chains is proposed. Through extensive simulations it is demonstrated that the proposed DWT-based
joint antenna selection has significant improvement of the capacity for both i.i.d and correlated MIMO channels, while requiring
only a minor hardware overhead and low computational complexity for the DWT operations. Moreover, it is shown that the capacity
associated with DWT-based JAS is higher than the system employing DWT-based receive antenna selection (RAS) only. This is
achieved in i.i.d. and correlated MIMO channels. 相似文献
36.
The present study describes the effects of glycerol, relative humidity (RH) and the minor components of corn flour on mechanical and thermal properties of native flour, defatted flour, and starch‐based materials. The kinetic of retrogradation for these different materials were dissimilar. For all samples, strain at break shows a maximum value as a function of RH followed by a decrease, explained by the appearance of water and glycerol clusters. Starch controls the mechanical properties of corn flour‐based material and their variations with temperature and humidity. Lipid and protein have negative effect on mechanical properties of thermoplastic flour toward starch but they did not have a plasticizing effect on the physicochemical behavior of the matrix. Tgs decreased as a result of water content increase. 相似文献
37.
Trabelsi Ali Rezgui Mohamed Ali 《The International Journal of Advanced Manufacturing Technology》2020,106(7):2829-2841
The International Journal of Advanced Manufacturing Technology - The paper discusses a generic procedure for the parameter design of product and process development using planned and non-planned... 相似文献
38.
39.
Alsaedi Marwan Abdullah Abnisa Faisal Alaba Peter Adeniyi Farouk Hamisu Umar 《Clean Technologies and Environmental Policy》2022,24(4):1285-1300
Clean Technologies and Environmental Policy - The Saudi economy is driven by the energy sector which mainly derived from petroleum-based resources. Besides export, the Kingdom’s consumption... 相似文献
40.
Hussein Abulkasim Ahmed Farouk Hanan Alsuqaih Walaa Hamdan Safwat Hamad S. Ghose 《Quantum Information Processing》2018,17(11):316
Recently, Wang and Ma (Quantum Inf Process 16(5):130, 2017) proposed two interesting quantum key agreement protocols with a single photon in both polarization and spatial-mode degrees of freedom. They claimed that the privacy of participants’ secret keys in the multiparty case is protected against dishonest participants. However, in this paper, we prove that two dishonest participants can deduce the secret key of an honest one using a fake sequence of single photons, without being detected. Also, we propose an additional security detection process to avoid the security loophole in their protocol. 相似文献