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Y Allieu G Asencio H Bahri M Pascal R Gomis N Louchahi 《Canadian Metallurgical Quarterly》1983,2(4):341-344
The authors used Hunter's technique to treat 16 cases of fixed-flexion deformity of the finger (with irreducible flexion of the joint greater then 70 degrees), secondary to lesions of the flexor tendons. The flexion deformity was corrected in 11 of the 16 cases, and active movement greater than 70 degrees was obtained in only 7 cases. Technical difficulties (particularly cutaneous problems), frequent complications, prolonged reeducation are the reasons that the indications for its use are exceptional, and why there is need for excellent cooperation by the patient. 相似文献
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Somayeh Keypour Hasan Rafati Hossain Riahi Fateme Mirzajani Mohammad Fata Moradali 《Food chemistry》2010
Ganoderma lucidum is used as a health food and medicine in Far East and produces different ganoderic acids which are well known for their valuable bioactivities. In this study, two different strains of G. lucidum from Iran and China were investigated for ganoderic acids, using reversed phase HPLC (RP-HPLC) in combination with UV and electrospray ionisation-mass spectrometry (ESI-MS). The results showed a relatively low intensity ganoderic acid C2 peak in the chromatogram of the Iranian sample. However, three high intensity peaks attributed to the well known ganoderic acids including ganoderic acids T, Me and H from the Chinese strain. These findings clearly indicated that different strains of G. lucidum could posses a range of active compounds and hence, bioactivities. Moreover, the variation in the triterpenoid components encourages more studies on the rest of bioactive molecules, and also different strains grown in a variety of climatic and geographical conditions. 相似文献
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Fateme Faraji Daneshgar Maghsoud Abbaspour 《International Journal of Communication Systems》2019,32(13)
Botnet is a distributed platform for illegal activities severely threaten the security of the Internet. Fortunately, although their complicated nature, bots leave some footprints during the C&C communication that have been utilized by security researchers to design detection mechanisms. Nevertheless, botnet designers are always trying to evade detection systems by leveraging the legitimate P2P protocol as C&C channel or even mimicking legitimate peer‐to‐peer (P2P) behavior. Consequently, detecting P2P botnet in the presence of normal P2P traffic is one of the most challenging issues in network security. However, the resilience of P2P botnet detection systems in the presence of normal P2P traffic is not investigated in most proposed schemes. In this paper, we focused on the footprint as the most essential part of a detection system and presented a taxonomy of footprints utilized in behavioral P2P botnet detection systems. Then, the resilience of mentioned footprints is analyzed using three evaluation scenarios. Our experimental and analytical investigations indicated that the most P2P botnet footprints are not resilient to the presence of legitimate P2P traffic and there is a pressing need to introduce more resilient footprints. 相似文献
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Jameson cell is a flotation device that has unique characteristics for fine grained particles, and thus, it has more than three hundred applications in worldwide. On the contrary, the flotation performance of the cell decreases by coarser feeding, which limits the application of the Jameson cell. It has been figured out that the main reason for the performance decrease for coarse particle is turbulence which occurs at the outlet of the downcomer in the Jameson cell. Therefore, the aim of this study was to prevent the performance decrease in the Jameson cell by modifying the downcomer which was implemented by taking into account the fluid mechanics law and mathematical modelling. The modified downcomer, which can be called as diffuser, can provide better aggregate stability and less turbulence at the end of the downcomer. Thus, theoretically the better performance was obtained by the use of the new form of downcomer. In addition, a series of experiments were carried out to verify the success of the modified downcomer. According to the results, velocity gradient (G) decreased to 640?s?1 from 671?s?1 by using the modified downcomer, and the maximum floatable particle size increased to 255?µm from 225?µm. 相似文献
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Water Resources Management - One of the undeniable requirements in hydrological forecasting and water resources studies is the availability of reliable information. Due to the various reasons, time... 相似文献
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Many water resources optimization problems involve conflicting objectives which the main goal is to find a set of optimal solutions on, or near to, Pareto front. In this study a multi-objective water allocation model was developed for optimization of conjunctive use of surface water and groundwater resources to achieve sustainable supply of agricultural water. Here, the water resource allocation model is based on simulation-optimization (SO) modeling approach. Two surrogate models, namely an Artificial Neural Network model for groundwater level simulation and a Genetic Programming model for TDS concentration prediction were coupled with NSGA-II. The objective functions involved: 1) minimizing water shortage relative to the water demand, 2) minimizing the drawdown of groundwater level, and 3) minimizing the groundwater quality changes. According to the MSE and R2 criteria, the results showed that the surrogate models for prediction of groundwater level and TDS concentration performed favorably in comparison to the measured values at the number of observation wells. In Najaf Abad plain case study, the average drawdown was limited to 0.18 m and the average TDS concentration also decreased from 1257 mg/lit to 1229 mg/lit under optimal conditions. 相似文献
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Fateme Salehi Mohammad‐Hassan Majidi Naaser Neda 《International Journal of Communication Systems》2018,31(12)
The abundant benefits of Orthogonal Frequency‐Division Multiplexing and its high flexibility have resulted in its widespread applications in many telecommunication standards. One important parameter for improving wireless system's efficiency is the accurate estimation of channel state information. In the literatures, many techniques have been studied in order to estimate the channel state information. Nowadays, the techniques based on intelligent algorithms such as genetic algorithm and particle swarm optimization (PSO) have attracted attention of researchers. With a very low pilot overhead, these techniques are able to estimate the channel frequency response properly only using the received signals. Unfortunately, each of these techniques suffers a common weakness: they have a slow convergence rate. In this paper, a new intelligent and different method has been presented for channel estimation using learning automata, entitled LA estimator, where the learning automata are search agents, and each pair is responsible for searching 1 complex coefficient of the channel frequency response. This method can achieve an accurate channel estimation with a moderate computational complexity in comparison with GA and PSO estimators. Furthermore, with higher convergence rate, our proposed method is capable of providing the same performance as GA and PSO. For a 2‐path fast fading channel, simulation results demonstrate the robustness of our proposed scheme according to the bit error rate and the mean square error. 相似文献
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Changes in functionality of wheat flour blended with hydrocolloids (alginate, locust bean gum, guar gum, and xanthan) were investigated. Microvisco-amylograph and flour quality analyses were conducted and showed significant (p < 0.05) differences among samples. Correlation of microvisco-amylograph values with other parameters showed that microvisco-amylograph parameters (final viscosity, setback, breakdown, etc.) showed significant (p < 0.05) correlation with other parameters. Microvisco-amylograph breakdown was significantly (p < 0.05) and positively correlated with dough strength and loaf volume. Microvisco-amylograph end of cooling, final viscosity, setback, and breakdown were identified as valuable for determination of flour, dough, and bread qualities as impacted by addition of hydrocolloids. 相似文献