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1.
Ramtin ShamsAuthor Vitae Parastoo SadeghiAuthor Vitae 《Journal of Parallel and Distributed Computing》2011,71(4):584-593
A model for the computational cost of the finite-difference time-domain (FDTD) method irrespective of implementation details or the application domain is given. The model is used to formalize the problem of optimal distribution of computational load to an arbitrary set of resources across a heterogeneous cluster. We show that the problem can be formulated as a minimax optimization problem and derive analytic lower bounds for the computational cost. The work provides insight into optimal design of FDTD parallel software. Our formulation of the load distribution problem takes simultaneously into account the computational and communication costs. We demonstrate that significant performance gains, as much as 75%, can be achieved by proper load distribution. 相似文献
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Parastoo Mohagheghi Wasif Gilani Alin Stefanescu Miguel A. Fernandez Bjørn Nordmoen Mathias Fritzsche 《Software and Systems Modeling》2013,12(3):619-639
There have been few experience reports from industry on how Model-Driven Engineering (MDE) is applied and what the benefits are. This paper summarizes the experiences of three large industrial participants in a European research project with the objective of developing techniques and tools for applying MDE on the development of large and complex software systems. The participants had varying degrees of previous experience with MDE. They found MDE to be particularly useful for providing abstractions of complex systems at multiple levels or from different viewpoints, for the development of domain-specific models that facilitate communication with non-technical experts, for the purposes of simulation and testing, and for the consumption of models for analysis, such as performance-related decision support and system design improvements. From the industrial perspective, a methodology is considered to be useful and cost-efficient if it is possible to reuse solutions in multiple projects or products. However, developing reusable solutions required extra effort and sometimes had a negative impact on the performance of tools. While the companies identified several benefits of MDE, merging different tools with one another in a seamless development environment required several transformations, which increased the required implementation effort and complexity. Additionally, user-friendliness of tools and the provision of features for managing models of complex systems were identified as crucial for a wider industrial adoption of MDE. 相似文献
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Sophie C. Cox Parastoo Jamshidi Liam M. Grover Kajal K. Mallick 《Journal of materials science. Materials in medicine》2014,25(1):37-46
The use of tissue engineered biodegradable porous scaffolds has become an important focus of the biomedical research field. The precursor materials used to form these structures play a vital role in their overall performance thus making the study and synthesis of these selected materials imperative. The authors present a comparison and characterisation of hydroxyapatite (HA), a popular calcium phosphate (CaP) biomaterial, synthesised by an aqueous precipitation (AP) method. The influence of various reaction conditions on the phase, crystallinity, particle size as well as morphology, molecular structure, potential in-vivo bioactivity and cell viability were assessed by XRD, SEM and TEM, FTIR, a simulated body fluid (SBF) test and a live/dead assay using MC3T3 osteoblast precursor cells, respectively. Naturally carbonated nanoparticles of HA with typically needle-like morphology were synthesised by the reported AP method. Initial pH was found to influence the crystallisation process and determine the CaP phase formed as well as the resultant particle and crystallite sizes. A marked change in particle morphology was also observed above pH 9. The use of toluene as a replacement solvent for water up to 60 % was found to reduce the crystallinity of as-synthesised HA. This has marked influence on the effect of ethanolamine (5 wt%), which was found to improve HA crystallinity. SEM and EDS were used to confirm the growth of carbonated apatite on the surface of HA pellets immersed in SBF for up to 28 days. Cell culture results revealed viable cells on all samples where pH was controlled and maintained at 10–11 during precipitation, including those that used ethanolamine and toluene in preparation. When the initial alkali pH was not maintained non-viable cells were observed on HA substrates. 相似文献
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Gwen J. Leusink David D. Kitts Parastoo Yaghmaee Tim Durance 《Journal of food science》2010,75(3):C311-C316
ABSTRACT: In this study, cranberries were dried by vacuum-microwave drying (VMD), freeze-drying (FD), or hot air-drying (AD), to compare the effects of different drying processes on both physical changes as well as the retention of bioactive components in dried samples. Total porosity (%) and average pore radius of dehydrated cranberries were greater using VMD compared to FD and AD (P < 0.05). Crude methanol cranberry powdered extracts were fractionated by solid phase extraction (SPE) into organic acid-, total phenolics-, anthocyanin-, or proanthocyanidin-enriched extracts, respectively. The chemical composition of the 60% acidified methanol fractions contained cyanidin-3-galactoside, cyanidin-3-arabinoside, peonidin-3-galactoside, and peonidin-3-arabinoside, as assessed by HPLC. Antioxidant activities of cranberry fractions were measured using chemical ORAC and ABTS methods. The 60% acidified methanol fraction had a significantly higher (P < 0.05) antioxidant potential than the other chemical fractions, which was largely attributed to the relatively higher anthocyanin content. In general, vacuum-microwave drying and freeze-drying resulted in similar retention of anthocyanins and antioxidant activity, which were both relatively higher (P < 0.05) than that recovered from cranberries dried by hot air drying. 相似文献
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Wanjun Liu Yu Shrike Zhang Marcel A. Heinrich Fabio De Ferrari Hae Lin Jang Syeda Mahwish Bakht Mario Moisés Alvarez Jingzhou Yang Yi‐Chen Li Grissel Trujillo‐de Santiago Amir K. Miri Kai Zhu Parastoo Khoshakhlagh Gyan Prakash Hao Cheng Xiaofei Guan Zhe Zhong Jie Ju Geyunjian Harry Zhu Xiangyu Jin Su Ryon Shin Mehmet Remzi Dokmeci Ali Khademhosseini 《Advanced materials (Deerfield Beach, Fla.)》2017,29(3)
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Elevated concentrations of hazardous metals in aquatic systems are known to threaten human health. Mobility, bioavailability, and toxicity of metals are controlled by chemical speciation, a dynamic process. Understanding metal behavior is limited by the lack of analytical methods that can provide rapid, sensitive, in situ measurements. While electrochemistry shows promise, it is limited by its temporal resolution and the necessity for Hg modified electrodes. In this letter, we apply fast-scan deposition-stripping voltammetry at carbon-fiber microelectrodes for in situ measurements of Cu(II). We present a novel, Hg-free technique that can measure Cu(II) with ppb sensitivity at 100 ms temporal resolution. 相似文献
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Pourrezaei P Drzewicz P Wang Y Gamal El-Din M Perez-Estrada LA Martin JW Anderson J Wiseman S Liber K Giesy JP 《Environmental science & technology》2011,45(19):8452-8459
Coagulation/flocculation (CF) by use of alum and cationic polymer polyDADMAC, was performed as a pretreatment for remediation of oil sands process-affected water (OSPW). Various factors were investigated and the process was optimized to improve efficiency of removal of organic carbon and turbidity. Destabilization of the particles occurred through charge neutralization by adsorption of hydroxide precipitates. Scanning electron microscope images revealed that the resultant flocs were compact. The CF process significantly reduced concentrations of naphthenic acids (NAs) and oxidized NAs by 37 and 86%, respectively, demonstrating the applicability of CF pretreatment to remove a persistent and toxic organic fraction from OSPW. Concentrations of vanadium and barium were decreased by 67-78% and 42-63%, respectively. Analysis of surface functional groups on flocs also confirmed the removal of the NAs compounds. Flocculation with cationic polymer compared to alum, caused toxicity toward the benthic invertebrate, Chironoums dilutus, thus application of the polymer should be limited. 相似文献
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Heydari Masoud Rostami Parastoo Roshani Saeed 《Wireless Personal Communications》2019,108(3):1571-1594
Wireless Personal Communications - Over the past few years, Internet of Things security has attracted the attention of many researchers due to its challenging and constrained nature. Particularly... 相似文献
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Parastoo Pourashouri Bahare Shabanpour Santiago P. Aubourg Javad Daghigh Rohi & Ali Shabani 《International Journal of Food Science & Technology》2009,44(8):1503-1509
The effect of preliminary ascorbic and citric acid (AA and CA, respectively) soaking treatments on the rancidity development in Wels catfish ( Silurus glanis ) fillets during further frozen storage (−18 °C; up to 6 months) was studied. Rancidity development was measured by biochemical quality indices (formation of free fatty acids, peroxides and secondary oxidation products) and compared with sensory analysis (appearance, rancid odour and consistency) and general chemical analyses (pH, expressible moisture and heme iron contents). When compared with control samples, AA- and CA-treated samples showed a lower ( P < 0.05) formation of primary and secondary lipid oxidation compounds that was corroborated by a longer ( P < 0.05) shelf-life time as a result of a lower rancid odour formation. According to these results, control samples showed a higher ( P < 0.05) heme iron breakdown (months 3–6) and a lower ( P < 0.05) water-holding capacity (higher expressible moisture value) (month 6). 相似文献