Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 41 )

2018 ( 33 )

2017 ( 17 )

2016 ( 27 )

Custom range...

Search Results: 1 - 10 of 2158 matches for " Karim Saber "
All listed articles are free for downloading (OA Articles)
Page 1 /2158
Display every page Item
A completeness result for the simply typed $λμ$-calculus
Karim Nour,Khelifa Saber
Mathematics , 2009,
Abstract: In this paper, we define a realizability semantics for the simply typed $\lambda\mu$-calculus. We show that if a term is typable, then it inhabits the interpretation of its type. This result serves to give characterizations of the computational behavior of some closed typed terms. We also prove a completeness result of our realizability semantics using a particular term model.
A semantics of realisability for the classical propositional natural deduction
Karim Nour,Khelifa Saber
Mathematics , 2009,
Abstract: In this paper, we introduce a semantics of realisability for the classical propositional natural deduction and we prove a correctness theorem. This allows to characterize the operational behaviour of some typed terms.
A semantical proof of the strong normalization theorem for full propositional classical natural deduction
Karim Nour,Khelifa Saber
Mathematics , 2009,
Abstract: We give in this paper a short semantical proof of the strong normalization for full propositional classical natural deduction. This proof is an adaptation of reducibility candidates introduced by J.-Y. Girard and simplified to the classical case by M. Parigot.
Confluency property of the call-by-value $λμ^{\wedge \vee}$-calculus
Karim Nour,Khelifa Saber
Mathematics , 2009,
Abstract: In this paper, we introduce the $\lambda\mu^{\wedge \vee}$- call-by-value calculus and we give a proof of the Church-Rosser property of this system. This proof is an adaptation of that of Andou which uses an extended parallel reduction method and complete development.
Experimental Investigation of Effects of Electric Operating Parameters on Pulsed Corona Discharges in Humid Air at Atmospheric Pressure  [PDF]
Hasna Guedah, Alyen Abahazem, Nofel Merbahi, Mohamed Yousfi, Karim Saber, Ahmed Ihlal
Journal of Analytical Sciences, Methods and Instrumentation (JASMI) , 2018, DOI: 10.4236/jasmi.2018.84005
The present work is devoted to electrical and optical study of a point-plane atmospheric pressure corona discharge reactor in humid air powered by pulsed high voltage supply. The corona current and the injected energy are analyzed as a function of several parameters such as applied voltage and humidity rate. Then, investigations based on emission spectroscopy analysis were used in UV range (from 200 nm to about 400 nm). The main observed excited species were the second positive (SPS), the first negative (FNS) systems and OH(A-X) rotational bands. The latter band was used to simulate the rotational temperature (Tr), whereas the N2+ (FNS) band was used to determine the vibrational temperature (Tv). The electron temperature (Te ) is determined from the ratio of line intensities of the spectral bands of both N2+ FNS at 391.4 nm and N2SPS at 394.4 nm. The rotational, vibrational and electronic temperatures are analyzed as a function of above parameters (applied voltage, frequency and hygrometry rate) near the anodic tip. As well we study the axial variation of electronic temperature for a fixed applied voltage at 6.4 kV, frequency at 10 kHz and 100% of humidity. It is found that the rotational, vibrational and electronic temperatures increased with increasing applied voltage, frequency and humidity rate. The increase of rate hygrometry for an inter-electrode distance fixed at 10 mm causes an increase in both the amplitude of the corona current discharge and the energy injected in corona discharge. This is indicative of more intense reactive plasma while increasing hygrometry rate.
Skeletal extension rate of the reef building coral Porites species from Aqaba and their environmental variables  [PDF]
Saber Al-Rousan
Natural Science (NS) , 2012, DOI: 10.4236/ns.2012.49097
Abstract: Annual skeletal extension rates of the sclera-actinian corals Porites species were investigated in 32 colonies from the northern Gulf of Aqaba fringing reef at various depths (1 - 42 m). All corals reveal clear and regular skeletal density banding patterns. Results showed that the high-density annual growth bands were formed during winter and the low-density annual growth bands during summer. The mean annual extension rates of the studied corals reveal a large inter-colony variability with values ranged between 2.36 to 20.0 mm/year. While a general trend of decreasing coral extension rate with depth was observed and best explained by a simple exponential model, the rates clustered into two groups: 10.86 ± 2.54 mm/year in water depths less than 10 m, and 5.23 ± 1.99 mm/year below 12 m. Light intensity seems to be the primary environmental factor responsible for decreasing coral extension rate with depth since the effect of other environmental parameters could be neglected from the Gulf of Aqaba. Time series record of the mean annual coral extension rate showed a slight increasing linear trend which could be linked to increase seawater temperature over the period of time represented.
Higher-Order Statistics for Automatic Weld Defect Detection  [PDF]
Sara Saber, Gamal I. Selim
Journal of Software Engineering and Applications (JSEA) , 2013, DOI: 10.4236/jsea.2013.65031

Image processing and image analysis are the main aspects for obtaining information from digital image owing to the fact that this techniques give the desired details in most of the applications generally and Non-Destructive testing specifically. This paper presents a proposed method for the automatic detection of weld defects in radiographic images. Firstly, the radiographic images were enhanced using adaptive histogram equalization and are filtered using mean and wiener filters. Secondly, the welding area is selected from the radiography image. Thirdly, the Cepstral features are extracted from the Higher-Order Spectra (Bispectrum and Trispectrum). Finally, neural networks are used for feature matching. The proposed method is tested using 100 radiographic images in the presence of noise and image blurring. Results show that in spite of time consumption, the proposed method yields best results for the automatic detection of weld defects in radiography images when the features were extracted from the Trispectrum of the image.

Conceptual Analysis and Fieldwork in Macroeconometric Methodology: Modeling Unemployment, Inflation and Production  [PDF]
Karim Errouaki
Technology and Investment (TI) , 2014, DOI: 10.4236/ti.2014.53015

The recent failure of commonly accepted, inductive, econometric models to provide insights into real, macroeconomic phenomenon during economic crises has provoked a debate concerning contemporary econometric methodology. Based on the foundations laid by Haavelmo, and Hollis and Nell, an assessment of Edward J. Nell’s (1998) “unifying methodological framework” (UMF) is offered. Nell’s UMF places socioeconomic institutions and interdependencies, and technological realities as basis of analysis. Using “conceptual analysis” and “fieldwork” Nell presents an alternative to generally accepted, mainstream, econometric methodology. The purpose of this paper is to look at some examples of the way, and this can help develop useful theory and improve macroeconometric model building. Applying Nell’s UMF to unemployment, inflation, and production reveals a methodological advance that promises more realistic insights into macroeconomic phenomena than is offered by contemporary, mainstream, econometric models.

Isolated loss of inferior pubic ramus: a case report
Aly Saber
Journal of Medical Case Reports , 2008, DOI: 10.1186/1752-1947-2-202
Abstract: A fit and otherwise healthy 35-year-old woman presented with pain in the left lower limb of 6 months duration. She sought advice from an orthopedic surgeon and was referred for exclusion of a primary soft tissue neoplasm. There was no history of trauma, chronic medical illness or surgical operations. Full systemic examination, laboratory investigations and whole body imaging showed no soft tissue swelling or any other bony defects. Isolated loss of the left inferior pubic ramus and thinning of the superior pubic ramus were detected, raising the question of whether the lesion was a secondary osteolytic lesion, a primary osteolytic lesion or due to endocrine disease.Isolated loss of the inferior pubic ramus with no concomitant bony or soft tissue anomalies is previously unreported. To the best of the author's knowledge, this finding has not been described previously.The development of the pelvic girdles has been poorly investigated and reported evidence suggests that the regulation of ilium development is different from the development of ischium and pubis [1].An extensive study was carried out to investigate the prenatal development and mineralization of ossification centers in the pelvic bone (ilium, ischium, and pubic bone) using radiography and optical density measurements on human fetuses. The mineral density of the pelvic bone increases with age and the mineralization rate changes throughout fetal life [2]. The hip bone is ossified from eight centers: three primary, one each for the ilium, ischium, and pubis; and five secondary, one each for the crest of the ilium, the anterior inferior spine, the tuberosity of the ischium, the pubic symphysis, and one or more for the Y-shaped piece at the bottom of the acetabulum. At birth, the three primary centers are quite separate and by the seventh or eighth year, the inferior rami of the pubis and ischium are almost completely united by bone [3].Delayed ossification of limbs and girdles is an expression of several congeni
Evaluation of alteration in mucogingival line location following use of subepithelial connective tissue graft
Saber Fariba
Indian Journal of Dental Research , 2010,
Abstract: Aim and Objective : The aim of this study is to evaluate the positional changes that occur in mucogingival line following the use of subepithelial connective tissue graft (SCTG). Materials and Methods : In 19 Miller class I or II gingival recession defects, distance between mucogingival line (MGL) and cemento-enamel junction, also width of keratinized and attached gingiva, and clinical attachment level were measured. SCTG were used for covering the exposed roots. A fore mentioned parameters were repeated at 3, 6 and 12 months after surgery and alterations were measured. Paired t test was used to analyze the results. Results : MGL had been moved in coronal direction (4.39 ± 0.77 mm on average) during surgical approach. After 1 year, MGL shifted 2.11 ± 0.7 mm apically. In accordance with this apical shift, a significant increase in the width of keratinized and attached gingival width (2.89 ± 0.63 mm and 2.82 ± 0.5 mm, respectively) was seen (P < 0.05). Conclusion : MGL tended to revert back to its original position following the use of SCTG, and this reversion is accompanied with an increase in the keratinized and attached gingival width.
Page 1 /2158
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.