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101.
Multi-objective OLSR for proactive routing in MANET with delay,energy, and link lifetime predictions
Zhihao Guo Shahdi Malakooti Shaya Sheikh Camelia Al-Najjar Behnam Malakooti 《Applied Mathematical Modelling》2011,35(3):1413-1426
In this paper, we develop a multi-objective approach for proactive routing in a Mobile Ad Hoc Network (MANET). We consider three routing objectives: minimizing average end-to-end delay, maximizing network energy lifetime, and maximizing packet delivery ratio. Accordingly, we develop three routing metrics: mean queuing delay on each node, energy cost on each node, and link stability on each link. For the proposed multi-objective approach, we develop efficient prediction methods: (a) predicting queuing delay and energy consumption using double exponential smoothing, and (b) predicting residual link lifetime using a heuristic of the distributions of the link lifetimes in MANET. Extensive simulation (by using ns2) is performed for the comparison of this multi-objective OLSR with existing OLSRs. The results show that the multi-objective OLSR is effective in finding optimal routing by tradeoffs among proposed objectives. 相似文献
102.
The optimal control of solidification in metal casting is considered. The underlying mathematical model is based on a three-dimensional
two-phase initial-boundary value problem of the Stefan type. The study is focused on choosing a cost functional in the optimal
control of solidification and choosing a difference scheme for solving the direct problem. The results of the study are described
and analyzed. 相似文献
103.
A. V. Albu A. F. Albu V. I. Zubov 《Computational Mathematics and Mathematical Physics》2011,51(5):762-780
The gradient of the cost functional in a discrete optimal control problem for metal solidification in metal casting is exactly
calculated. In contrast to previous studies, the object under analysis has a complex geometric shape. The mathematical model
for describing the solidification process is based on a three-dimensional two-phase initial-boundary value problem of the
Stefan type. Formulas for exact gradient evaluation are derived using the fast automatic differentiation technique. 相似文献
104.
Daniela IonitaMihaela Grecu Camelia UngureanuIoana Demetrescu 《Applied Surface Science》2011,257(21):9164-9168
The paper investigates the increase of anticorrosive and antimicrobial properties of a composite elaborated by coating TiAlZr with Ag nanoparticles. Silver nanoparticles (AgNPs) were synthesized by reducing silver salts using NaBH4, and were characterized using dynamic light scattering instrument to determine the size distribution. The morphological and elemental analysis of Ag nanoparticles on the TiAlZr surface were performed with scanning electron microscopy (SEM) and energy disperse spectroscopy (EDS). Antibacterial activity was evaluated on the basis of the inhibition of the growth of Escherichia coli bacteria, and of the electrochemical parameters from dynamic polarization tests performed in Ringers bioliquid.An empirical model of antibacterial effect of silver nanoparticles at biointerface in the presence of TiAlZr implant was discussed. 相似文献
105.
Andrei Medvedovici Florin Albu Abdelwaheb Hamdi Rachid Souane Lidia Kim Lucia Mutihac Jacques Vicens 《Journal of inclusion phenomena and macrocyclic chemistry》2011,71(3-4):545-555
The ESI?CMS and MS/MS behavior of functionalized calix[4]arenes (1?C5) has been studied in both positive and negative-ion mode. Liquid chromatography coupled to ESI?CMS has been successfully used for separation of the byproducts issuing from the functionalization pathways, through the application of a simple reversed phase mechanism. The ability of (1?C5) to host methyl esters of amino acids, tyrosine, tryptophan, phenylalanine, cysteine, valine, serine, leucine, isoleucine, and threonine has been evaluated by means of MS identification of the host?Cguest resulting in protonated molecular ions. The direct infusion within the ESI source of the solutions containing the two partners (i.e., calixarene and amino acid derivative) could act as a fast screening means for the evaluation of hosting capability. Only positive ionization may offer information about the host?Cguest complexes being formed. The influence of the excess of a partner in the infused solution strongly alters ionization yields, making quantitative approaches meaningless. Attempts to chromatographically isolate the host?Cguest complexes failed, probably due to the fact that interactions of the partners with the mobile and stationary phases are higher than the inclusion interactions. Structures consisting of combined fragments of the host?Cguest partners resulting from the collisional induced dissociation have not been observed. 相似文献
106.
Simona Morariu Maria Bercea Camelia Hulubei 《Journal of Macromolecular Science: Physics》2013,52(6):1108-1116
The viscoelastic behavior of poly(N-(4-formylphenoxy-4′-carbonylphenyl)maleimide-co-styrene) and poly(N-(4-carboxyphenyl)maleimide-co-styrene) in dimethylsulfoxide is investigated. The rheological parameters (elastic modulus, viscous modulus, loss tangent) were determined at different temperatures in the range 20°C–80°C. Poly(N-(4-carboxyphenyl)maleimide-co-styrene) exhibits a Newtonian behavior in the frequency range from 0.05 to 700 rad/s at all temperatures. For poly(N-(4-formylphenoxy-4′-carbonylphenyl)maleimide-co-styrene), a shear thinning behavior was observed at temperatures below 40°C (pseudoplastic behavior), whereas at higher temperatures the sample exhibits Newtonian flow throughout the studied frequencies range. The activation energies of the flow (calculated by using the zero shear viscosity values) give indications about the intensity of polymer-polymer interactions as a function of the maleimide monomer structure. 相似文献
107.
P. Granitzer K. Rumpf M. Venkatesan L. Cabrera A. G. Roca M. P. Morales P. Poelt M. Albu K. Ali M. Reissner 《Journal of nanoparticle research》2011,13(11):5685-5690
Mesoporous silicon is utilized to infiltrate quite monodisperse iron oxide nanoparticles into the pores. This semiconducting
matrix exhibits oriented pores, clearly separated from each other, with an average pore diameter of 55 nm. Iron oxide nanoparticles
of 8 nm and 5 nm in size which are coated with a surfactant are prepared by high temperature decomposition in the presence
of an organic precursor. The achieved nanocomposite consists of dispersed Fe3O4-nanoparticles within the pores and offers magnetic properties which are determined by the morphology of the silicon matrix
as well as by the distribution of the particles within the individual pores. Thus, the change of regime between a superparamagnetic
and a blocked state of the system can be tuned. Furthermore, magnetic anisotropy between the two magnetization directions,
normal and parallel to the sample surface, is observed due to the oriented and separated pores of the template which are quasi-regular
arranged. This porous silicon/magnetite composite with its adjustable magnetic properties is also of interest for possible
applications in biomedicine due to the low toxicity of both materials. 相似文献
108.
109.
110.
The paper contains the transmitted vibrations produce by shocks to the human bodies into the working space.There are the methods for measuring the vibration experiments transmitted through the shock of the human body by the foundation of forging hammer. There are the results given by the different sorts of accelerations into to special conditions of work in the working space. They are of the vibrometer adding the three directions accelerometer. In this way can be analyze taking into account the vibrations action over the human bodies under the action of the equipment in the working space produced by shocks. (© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献