An efficient and scalable plagiarism checking system using Bloom filters

With the easy access to the huge volume of articles available on the Internet, plagiarism is getting worse and worse. Most recent approaches proposed to address this problem usually focus on achieving better accuracy of similarity detection process. However, there are some real applications where plagiarized contents should be detected without revealing any information. Moreover, in such web-based applications, running time, memory consumption, communication and computational complexity should be also taken into account. In this paper, we propose a similar document detection system based on matrix Bloom filter, a new extension of standard Bloom filter. The experimental results on a real dataset show that the system can achieve 98% of accuracy. We also compare our approach with a method recently proposed for the same purpose. The results of the comparison show that the Bloom filter-based approach achieves much better performance than other in terms of the aforementioned factors.     

Short communication: effects of supplementation with pomegranate seed pulp on concentrations of conjugated linoleic acid and punicic acid in goat milk

The effects of feeding pomegranate seed pulp (PSP) on milk yield, milk composition, fatty acid profiles of milk fat, and blood metabolites were examined in this study. During a pretrial period, 27 multiparous southern Khorasan (Iran) cross-bred goats were fed a similar diet and dry matter intake, milk yield, and milk composition were recorded. After adaptation and based on pretrial records, the goats were randomly assigned to 1 of 3 experimental diets and were housed in individual stalls. Experimental diets included 0, 6, or 12% of PSP (dry matter basis) and were fed as total mixed rations ad libitum for a 45-d period. Diets were formulated to be isonitrogenous and isocaloric. Supplementation of PSP did not affect dry matter intake or average daily gain of goats. Milk yield was not affected by inclusion of PSP in the diet. Milk fat concentration of goats fed diets with 6 and 12% PSP increased, but milk fat yield, milk protein concentration, and milk solids-not-fat concentration of goats were not affected by diets. Feeding PSP did not affect blood glucose, cholesterol, urea N, triglyceride, or lipoproteins. Feeding goats a diet containing 12% PSP modified the milk fatty acid profile, including conjugated linoleic, punicic, and vaccenic acids.     

Excitation of Cy5 in self-assembled lipid bilayers using optical microresonators

Due to their sensitivity and temporal response, optical microresonators are used extensively in the biosensor arena, particularly in the development of label-free diagnostics and measurement of protein kinetics. In the present letter, we investigate using microcavities to probe molecules within biomimetic membranes. Specifically, a method for self-assembling lipid bilayers on spherical microresonators is developed and the bilayer-nature is verified. Subsequently, the microcavity is used to excite a Cy5-conjugated lipid located within the bilayer while the optical performance of the microcavity is characterized. The emission wavelength of the dye and the optical behavior of the microcavity agree with theoretical predictions.     

Shape memory alloy film damping for smart miniature systems

This paper presents a dynamic analysis of the free and forced vibration of a free-standing bridge of superelastic shape memory alloy TiNiCuCo film with ultra-low fatigue properties and evaluates its versatility for novel miniature scale damping applications. A thermodynamics-based finite element model is used to simulate the evolution of martensite phase fraction during load-induced martensitic phase transformation. The effects of pre-strain, strain rate and excitation load on the hysteresis of stress-strain characteristics are investigated in order to assess damping energies. The analysis is performed under non-isothermal conditions taking into account heat transfer and rate-dependence of release and absorption of latent heat. We show that damping energy can be maximized by applying an optimum pre-strain. A maximum damping capacity of 0.17 is determined for the case of complete stress-strain hysteresis loop during phase transformation.     

Experimental and numerical study of piston thermal management using piston cooling jet

This research investigates the effects of piston cooling jet (PCJ) on the temperature and heat transfer of a piston. A numerical model was developed by using the computational fluid dynamic approach in which the fluid and solid domains of the piston were coupled in a three-dimensional space. Two-phase flow of oil and air was also simulated. This method was used to analyze the effects of oil velocity and piston position on the heat transfer coefficient at the bottom of the piston as the new outcomes of this study. For the experiment, combustion heat flux on the piston was simulated in a test rig, and numerical results were validated. The results showed a linear relation between the oil jet velocity and the average of heat transfer coefficient at the bottom of the piston, and a periodic correlation between the piston’s vertical position and the average of heat transfer coefficient. The average of the piston crown temperature could be reduced to about 70 K by using the PCJ system, but this cooling method could create 50 K temperature gradient in the piston.     

High-efficiency mechanochemical synthesis of Strontium carbonate nanopowder from Celestite

In this study, the conversion of Celestite to SrCO₃ was studied by wet mechanochemical synthesis in a high-energy ball mill and treatment with Na₂CO₃. For this purpose, solid strontium carbonate and soluble Na₂SO₄ were obtained after wet milling of Celestite powder and sodium carbonate. The solid phase was washed with water at room temperature by filter pressing. X-Ray diffraction patterns showed that the SrCO₃ nanopowder was synthesized and conversion boosted with increasing the milling time up to 8 hours Also, Rietveld refinement analysis was used to calculate the fraction of SrCO₃ as well as structural properties of synthesized samples. It was found that initial Celestite could be converted to strontium carbonate with a purity more than 98% using high-energy milling without simultaneous heating. The optimum milling time was determined as 4 hours resulting in formation of nanopowders with an average particle size around 90 nm. Field Emission Scanning Electron Microscopy (FE-SEM), clearly showed the nanoscale structure of the synthesized powders.     

Microstructural evolution in damaged IN738LC alloy during various steps of rejuvenation heat treatments

IN738LC is one of the superior nickel base superalloys utilized at high temperatures in aggressive environments. However, experiencing high temperatures and stresses during service causes microstructure deterioration and degradation of mechanical properties in this alloy. To restore the microstructure and mechanical properties of the degraded alloy, rejuvenation heat treatments can be considered. In this study, the evolution of microstructural features in a creep damaged IN738LC superalloy during different stages of rejuvenation heat treatment cycles was investigated. During solution treatment stage, dissolution of coarsened γ′ precipitates, grain boundary films and transition zone around primary MC carbides took place. Solution treatment at high temperature led to lower volume fraction and smaller size of remnant γ′ precipitates and further dissolution of grain boundary films and caused MC carbides to be remained without the surrounding transition zone. In addition, fine γ′ precipitates formed during the subsequent cooling, namely cooling precipitates, were detected in higher contents after solutionizing at higher temperatures. It was found that slower cooling rates after solution treatment gave rise to coarser γ′ precipitates with higher volume fraction. Among all heat treatment cycles investigated, double solution treatment at 1190 °C/4 h/FC (furnace cooling) + 1120 °C/2 h/AC (air cooling) followed by aging at 845 °C/24 h/AC was successful to revert the microstructure back to its virgin state.     

Bloom filter applications in network security: A state-of-the-art survey

Undoubtedly, dealing with security issues is one of the most important and complex tasks various networks face today. A large number of security algorithms have been proposed to enhance security in various types of networks. Many of these solutions are either directly or indirectly based on Bloom filter (BF), a space- and time-efficient probabilistic data structure introduced by Burton Bloom in 1970. Obviously, Bloom filters and their variants are getting more and more consideration in network security area. This paper provides an up-to-date survey of the application of BFs and their variants to improve performance of the approaches proposed to address security problems with different types of networks.     

Production of a new platform based on fumed and mesoporous silica nanoparticles for enhanced solubility and oral bioavailability of raloxifene HCl

The purpose of the present study was to compare mesoporous and fumed silica nanoparticles (NPs) to enhance the aqueous solubility and oral bioavailability of raloxifene hydrochloride (RH). Mesoporous silica NPs (MSNs) and fumed silica NPs were used by freeze‐drying or spray‐drying methods. MSNs were obtained with different ratios of cetyltrimethylammonium bromide. Saturation solubility of the NPs was compared with the pure drug. The optimised formulation was characterised by scanning electron microscopy (SEM), X‐ray diffraction (XRD) and differential scanning calorimetry. The pharmacokinetic studies were done by oral administration of a single dose of 15 mg/kg of pure drug or fumed silica NPs of RH in Wistar rats. MSNs enhanced the solubility of RH from 19.88 ± 0.12 to 76.5 μg/ml. Freeze‐dried fumed silica increased the solubility of the drug more than MSNs (140.17 ± 0.45 μg/ml). However, the spray‐dried fumed silica caused about 26‐fold enhancement in its solubility (525.7 ± 93.5 μg/ml). Increasing the ratio of silica NPs enhanced the drug solubility. The results of XRD and SEM analyses displayed RH were in the amorphous state in the NPs. Oral bioavailability of NPs showed 3.5‐fold increase compared to the pure drug. The RH loaded fumed silica NPs prepared by spray‐drying technique could more enhance the solubility and oral bioavailability of RH.Inspec keywords: differential scanning calorimetry, mesoporous materials, freezing, nanofabrication, drug delivery systems, silicon compounds, drying, drugs, solubility, spraying, X‐ray diffraction, biomedical materials, scanning electron microscopy, nanoparticles, biochemistry, amorphous state, nanomedicineOther keywords: freeze‐dried fumed silica, spray‐dried, drug solubility, spray‐drying technique, fumed silica nanoparticles, mesoporous silica nanoparticles, aqueous solubility, mesoporous silica NPs, freeze‐drying, saturation solubility, differential scanning calorimetry, oral administration, fumed silica NPs     

Evaluating the core damage frequency of a TRIGA research reactor using risk assessment tool software

After all preventive and mitigative measures considered in the design of a nuclear reactor, the installation still represents a residual risk to the outside world. Probabilistic safety assessment (PSA) is a powerful method to survey the safety of nuclear reactors. In this study the occurrence frequency of different types of core damage states (CDS) which may potentially arise in Tehran Research Reactor (TRR) is evaluated by use of the recently developed risk assessment tool (RAT) software which has been designed and represented in the Safety Research Center of Shiraz University. RAT uses event trees and fault trees to evaluate the total final core damage frequency (CDF) through studying the frequencies of initiation events, and following their consequences has resulted in one type of the CDS. The criterion must be of the order of smaller than 1E−04 through IAEA standards for research reactors (IAEA-TECDOC-400, 1986). Results show that the total final CDF for TRR is of the order of 10⁻⁶, which meets the criterion of nuclear research reactor.