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11.
This paper deals with the problem of estimating a transmitted string X * by processing the corresponding string Y, which is a noisy version of X *. We assume that Y contains substitution, insertion, and deletion errors, and that X * is an element of a finite (but possibly, large) dictionary, H. The best estimate X + of X *, is defined as that element of H which minimizes the generalized Levenshtein distance D(X, Y) between X and Y such that the total number of errors is not more than K, for all X ∈H. The trie is a data structure that offers search costs that are independent of the document size. Tries also combine prefixes together, and so by using tries in approximate string matching we can utilize the information obtained in the process of evaluating any one D(X i , Y), to compute any other D(X j , Y), where X i and X j share a common prefix. In the artificial intelligence (AI) domain, branch and bound (BB) schemes are used when we want to prune paths that have costs above a certain threshold. These techniques have been applied to prune, for example, game trees. In this paper, we present a new BB pruning strategy that can be applied to dictionary-based approximate string matching when the dictionary is stored as a trie. The new strategy attempts to look ahead at each node, c, before moving further, by merely evaluating a certain local criterion at c. The search algorithm according to this pruning strategy will not traverse inside the subtrie(c) unless there is a “hope” of determining a suitable string in it. In other words, as opposed to the reported trie-based methods (Kashyap and Oommen in Inf Sci 23(2):123–142, 1981; Shang and Merrettal in IEEE Trans Knowledge Data Eng 8(4):540–547, 1996), the pruning is done a priori before even embarking on the edit distance computations. The new strategy depends highly on the variance of the lengths of the strings in H. It combines the advantages of partitioning the dictionary according to the string lengths, and the advantages gleaned by representing H using the trie data structure. The results demonstrate a marked improvement (up to 30% when costs are of a 0/1 form, and up to 47% when costs are general) with respect to the number of operations needed on three benchmark dictionaries. 相似文献
12.
Reham Hammad Reda Badr Aglan Shaymaa A. Mohammed Eman Abu-elnasr Awad Marwa A. Elsaid Hanan M. Bedair Seham K. Khirala Mohamed A Selim Asmaa A. Abo Elqasem Areej Rushdi Mohamed Ali Omaima I. Abo-Elkheir Eman F. Sanad Nadia M. Hamdy 《International journal of molecular sciences》2022,23(20)
Virus-related hepatocellular carcinoma (HCC) pathogenesis involves liver inflammation, therefore, despite successful treatment, hepatitis C virus (HCV) may progress to HCC from initiated liver cirrhosis. Cytotoxic T cells (Tcs) are known to be involved in HCV-related cirrhotic complications and HCC pathogenesis. The inhibitory checkpoint leukocyte-associated immunoglobulin-like receptor-1 (LAIR-1) is expressed on Tcs. Therefore, we aimed to determine whether the Tc expression level of LAIR-1 is associated with HCC progression and to evaluate LAIR-1 expression as a noninvasive biomarker for HCC progression in the context of liver cirrhosis related to HCV genotype 4 (G4) in Egyptian patients’ peripheral venous blood liquid biopsy. A total of 64 patients with HCC and 37 patients with liver cirrhosis were enrolled in this case-controlled study, and their LAIR-1 expression on Tc related to the progression of liver cirrhosis was examined and compared to that of the apparently healthy control group (n = 20). LAIR-1 expression was analyzed using flow cytometry. Results: The HCC group had significantly higher LAIR-1 expression on Tc and percentage of Tc positive for LAIR-1 (LAIR-1+Tc%) than the HCV G4-related liver cirrhosis group. LAIR-1+Tc% was correlated with the HCC surrogate tumor marker AFP (r = 0.367, p = 0.001) and insulin resistance and inflammation prognostic ratios/indices. A receiver operating characteristic (ROC) curve revealed that adding LAIR-1+Tc% to AFP can distinguish HCC transformation in the Egyptian patients’ cohort. Upregulated LAIR-1 expression on Tc could be a potential screening noninvasive molecular marker for chronic inflammatory HCV G4 related liver cirrhosis. Moreover, LAIR-1 expression on Tc may be one of the players involved in the progression of liver cirrhosis to HCC. 相似文献
13.
Medhat A. Nemitallah Mohamed A. Habib Hassan M. Badr Syed A. Said Aqil Jamal Rached Ben‐Mansour Esmail M. A. Mokheimer K. Mezghani 《国际能源研究杂志》2017,41(12):1670-1708
The increased level of emissions of carbon dioxide into the atmosphere due to burning of fossil fuels represents one of the main barriers toward the reduction of greenhouse gases and the control of global warming. In the last decades, the use of renewable and clean sources of energies such as solar and wind energies has been increased extensively. However, due to the tremendously increasing world energy demand, fossil fuels would continue in use for decades which necessitates the integration of carbon capture technologies (CCTs) in power plants. These technologies include oxycombustion, pre‐combustion, and post‐combustion carbon capture. Oxycombustion technology is one of the most promising carbon capture technologies as it can be applied with slight modifications to existing power plants or to new power plants. In this technology, fuel is burned using an oxidizer mixture of pure oxygen plus recycled exhaust gases (consists mainly of CO2). The oxycombustion process results in highly CO2‐concentrated exhaust gases, which facilitates the capture process of CO2 after H2O condensation. The captured CO2 can be used for industrial applications or can be sequestrated. The current work reviews the current status of oxycombustion technology and its applications in existing conventional combustion systems (including gas turbines and boilers) and novel oxygen transport reactors (OTRs). The review starts with an introduction to the available CCTs with emphasis on their different applications and limitations of use, followed by a review on oxycombustion applications in different combustion systems utilizing gaseous, liquid, and coal fuels. The current status and technology readiness level of oxycombustion technology is discussed. The novel application of oxycombustion technology in OTRs is analyzed in some details. The analyses of OTRs include oxygen permeation technique, fabrication of oxygen transport membranes (OTMs), calculation of oxygen permeation flux, and coupling between oxygen separation and oxycombustion of fuel within the same unit called OTR. The oxycombustion process inside OTR is analyzed considering coal and gaseous fuels. The future trends of oxycombustion technology are itemized and discussed in details in the present study including: (i) ITMs for syngas production; (ii) combustion utilizing liquid fuels in OTRs; (iii) oxy‐combustion integrated power plants and (iv) third generation technologies for CO2 capture. Techno‐economic analysis of oxycombustion integrated systems is also discussed trying to assess the future prospects of this technology. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
14.
15.
Abouhaswa A. S. Badr M. H. Nasr M. H. Elkholy M. M. El-Deen L. M. S. Turky Gamal M. Moustafa M. EL-Hamalawy A. A. 《Journal of Inorganic and Organometallic Polymers and Materials》2022,32(2):486-498
Journal of Inorganic and Organometallic Polymers and Materials - Cd1 ? xMnxFe2O4 (x?=?0, 0.25, 0.5, 0.75, 1) spinel ferrite nanoparticle samples were synthesized... 相似文献
16.
Use of irradiation to control foodborne pathogens and extend the refrigerated market life of rabbit meat 总被引:5,自引:0,他引:5
Badr HM 《Meat science》2004,67(4):541-548
This study set out to evaluate the microbiological status of rabbit meat and the possibility of using irradiation to control foodborne pathogenic bacteria and extend the refrigerated storage life of meat. Rabbit meat samples were γ irradiated at doses of 0, 1.5 and 3 kGy. The samples were stored at refrigeration temperature, then the effects of irradiation and storage on their microbiological, chemical and sensory properties were studied. Irradiation at 1.5 kGy significantly reduced the counts of Staphylococcus aureus, Listeria monocytogenes, Enterococcus faecalis and enterobacteriaceae but was not enough for complete elimination of Salmonella. However, 3 kGy dose reduced the counts of S. aureus, L. monocytogenes, E. faecalis and enterobacteriaceae by more than 3, 3, 1.4 and 4 log units, respectively, while Salmonella was not detected. On the other hand, irradiation at 1.5 and 3 kGy significantly reduced the counts of aerobic mesophilic bacteria, psychrophilic bacteria and molds and yeasts and prolonged the refrigerated shelf-life of samples to 12 and 21 days, respectively, compared to 6 days for non-irradiated controls. Irradiation of samples significantly increased their amounts of thiobarbituric acid reactive substances (TBARS) but had no significant effects on their total volatile nitrogen (TVN) contents, while storage significantly increased the TBARS and TVN for irradiated and non-irradiated samples. γ irradiation showed no significant effects on the sensory properties of raw meat. Moreover, fried burgers prepared from irradiated rabbit meat showed high sensory acceptability similar to those prepared from non-irradiated meat. 相似文献
17.
Badr Bassou Nolven Guilhaume Eduard Emil Iojoiu David Farrusseng Karine Lombaert Daniel Bianchi Claude Mirodatos 《Catalysis Today》2011,159(1):103-143
Following the development of a high-throughput (HT) methodology for the evaluation of diesel soot oxidation catalysts in a 16 parallel channels reactor, a library of over 60 catalysts was tested under optimized conditions. The catalyst compositions were chosen to include solids which specific properties like oxygen storage capacity, oxygen mobility and ionic conductivity. The key parameters for high activity appear related to the presence of active and mobile surface oxygen species, and to an appropriate catalyst particle size in order to favour the number of contacts with the soot. In contrast, high oxygen storage capacity and bulk oxygen ion mobility do not appear as relevant properties for high catalytic activity. Nine new formulations were found to perform better than the reference catalyst “high surface area (HSA) ceria” (Rhodia). 相似文献
18.
A novel multi‐component system containing poly(vinyl alcohol), lithium bromide, sulfuric acid, ethylene carbonate and hydroquinone was prepared using a solution‐casting technique. The presence of hydroquinone as a reducing agent in the inorganic–organic membrane structure thus produced was thought to lead to enhanced thermal stability of the membrane. The activation energy for the thermal decomposition of the product samples increased with increasing hydroquinone doping. The ionic conductivities of the films were determined from AC impedance measurements in the temperature range 300–373 K. The maximum conductivity was found to be 1.75 × 10?3 S cm?1 for a film doped with 4 wt% hydroquinone. The results give some insight into the potential utility of the membrane as a proton‐conducting solid polymer electrolyte. Copyright © 2011 Society of Chemical Industry 相似文献
19.
Solouma NH Youssef AB Badr YA Kadah YM 《IEEE transactions on bio-medical engineering》2002,49(9):1059-1067
A new system is proposed for tracking sensitive areas in the retina for computer-assisted laser treatment of choroidal neovascularization (CNV). The system consists of a fundus camera using red-free illumination mode interfaced to a computer that allows real-time capturing of video input. The first image acquired is used as the reference image and utilized by the treatment physician for treatment planning. A grid of seed contours over the whole image is initiated and allowed to deform by splitting and/or merging according to preset criteria until the whole vessel tree is demarcated. Then, the image is filtered using a one-dimensional Gaussian filter in two perpendicular directions to extract the core areas of such vessels. Faster segmentation can be obtained for subsequent images by automatic registration to compensate for eye movement and saccades. An efficient registration technique is developed whereby some landmarks are detected in the reference frame then tracked in the subsequent frames. Using the relation between these two sets of corresponding points, an optimal transformation can be obtained. The implementation details of proposed strategy are presented and the obtained results indicate that it is suitable for real-time location determination and tracking of treatment positions. 相似文献
20.
YJ Chwae IH Choi DS Kim EC Shin DH Kwon SJ Kim JD Kim 《Canadian Metallurgical Quarterly》1998,63(3):147-152
Videolaparoscopic cholecystectomy is considered the treatment of choice for simple cholelithiasis. Now many surgeons consider the laparscopic procedure usable also in the complicated biliary lithiasis like acute cholecystitis and choledocholithiasis. The authors report their recent experience of the laparoscopic treatment of biliary lithiasis, regarding 221 non-selected patients (69% symptomatic cholelithiasis, 20% chronic cholecystitis, 4.5% acute cholecystitis, 4.5% coledocolithiasis, 2% hydrops). The diagnostic-therapeutic protocol and the results are described and compared with the beginning of their experience, when they treated only symptomatic gallbladder stone disease, and with the reports of the literature. The authors concluded that the laparoscopic procedure is a good chance for the surgeon in the treatment of all cases of benign biliary disease. But, in particular for patients with choledocholithiasis, he has be able to know all the diagnostic and therapeutic possibilities, to choose the best in every single case. 相似文献