Search results for: Sadek Salah
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 205

Search results for: Sadek Salah

115 Consumers Rights during COVID-19 Pandemic Time: Evidence from Libya

Authors: Sabri Gabran Mohammed Elkrghli, Salah A. Mohamed Abdulgader

Abstract:

Given the emergence and the spreading of the Covid-19 pandemic that swept the globe, it was necessary to address the issue of consumer rights in such unprecedented circumstances. Libyan consumers have been targeted in this study with the aim to measure their attitudes towards the extent to which their rights, as consumers of foodstuff, have been secured during the Covid-19 pandemic. The recommended sample size was randomly selected (384) local participants. Out of this number, only a validated number of (267) responses were deemed valid for the analysis phase. The instrument of this research was developed based on the extant published literature on consumer rights. The study concluded with a set of key results; the most important result is that consumer rights of foodstuffs were below the satisfactory level. Theoretical and practical implications have emerged from the study. The most important implication is that customers of foodstuffs need more protection in Libya. This issue should be given greater importance, especially in the light of contemporary environmental challenges such as the outbreak of Covid-19. Designing and conducting global and local awareness campaigns is another significant advice suggested by this study. Finally, the research concluded with limitations and put forward some future avenues.

Keywords: consumers rights, foodstuffs, COVID-19, Libya

Procedia PDF Downloads 128
114 Agent/Group/Role Organizational Model to Simulate an Industrial Control System

Authors: Noureddine Seddari, Mohamed Belaoued, Salah Bougueroua

Abstract:

The modeling of complex systems is generally based on the decomposition of their components into sub-systems easier to handle. This division has to be made in a methodical way. In this paper, we introduce an industrial control system modeling and simulation based on the Multi-Agent System (MAS) methodology AALAADIN and more particularly the underlying conceptual model Agent/Group/Role (AGR). Indeed, in this division using AGR model, the overall system is decomposed into sub-systems in order to improve the understanding of regulation and control systems, and to simplify the implementation of the obtained agents and their groups, which are implemented using the Multi-Agents Development KIT (MAD-KIT) platform. This approach appears to us to be the most appropriate for modeling of this type of systems because, due to the use of MAS, it is possible to model real systems in which very complex behaviors emerge from relatively simple and local interactions between many different individuals, therefore a MAS is well adapted to describe a system from the standpoint of the activity of its components, that is to say when the behavior of the individuals is complex (difficult to describe with equations). The main aim of this approach is the take advantage of the performance, the scalability and the robustness that are intuitively provided by MAS.

Keywords: complex systems, modeling and simulation, industrial control system, MAS, AALAADIN, AGR, MAD-KIT

Procedia PDF Downloads 209
113 Robust Numerical Scheme for Pricing American Options under Jump Diffusion Models

Authors: Salah Alrabeei, Mohammad Yousuf

Abstract:

The goal of option pricing theory is to help the investors to manage their money, enhance returns and control their financial future by theoretically valuing their options. However, most of the option pricing models have no analytical solution. Furthermore, not all the numerical methods are efficient to solve these models because they have nonsmoothing payoffs or discontinuous derivatives at the exercise price. In this paper, we solve the American option under jump diffusion models by using efficient time-dependent numerical methods. several techniques are integrated to reduced the overcome the computational complexity. Fast Fourier Transform (FFT) algorithm is used as a matrix-vector multiplication solver, which reduces the complexity from O(M2) into O(M logM). Partial fraction decomposition technique is applied to rational approximation schemes to overcome the complexity of inverting polynomial of matrices. The proposed method is easy to implement on serial or parallel versions. Numerical results are presented to prove the accuracy and efficiency of the proposed method.

Keywords: integral differential equations, jump–diffusion model, American options, rational approximation

Procedia PDF Downloads 92
112 Fuel Cells and Offshore Wind Turbines Technology for Eco-Friendly Ports with a Case Study

Authors: Ibrahim Sadek Sedik Ibrahim, Mohamed M. Elgohary

Abstract:

Sea ports are considered one of the factors affecting the progress of economic globalization and the international trade; consequently, they are considered one of the sources involved in the deterioration of the maritime environment due to the excessive amount of exhaust gases emitted from their activities. The majority of sea ports depend on the national electric grid as a source of power for the domestic and ships’ electric demands. This paper discusses the possibility of shifting ports from relying on the national grid electricity to green power-based ports. Offshore wind turbines and hydrogenic PEM fuel cell units appear as two typical promising clean energy sources for ports. As a case study, the paper investigates the prospect of converting Alexandria Port in Egypt to be an eco-friendly port with the study of technical, logistic, and financial requirements. The results show that the fuel cell, followed by a combined system of wind turbines and fuel cells, is the best choice regarding electricity production unit cost by 0.101 and 0.107 $/kWh, respectively. Furthermore, using of fuel cells and offshore wind turbine as green power concept will achieving emissions reduction quantity of CO₂, NOx, and CO emissions by 80,441, 20.814, and 133.025 ton per year, respectively. Finally, the paper highlights the role that renewable energy can play when supplying Alexandria Port with green energy to lift the burden on the government in supporting the electricity, with a possibility of achieving a profit of 3.85% to 22.31% of the annual electricity cost compared with the international prices.

Keywords: fuel cells, green ports, IMO, national electric grid, offshore wind turbines, port emissions, renewable energy

Procedia PDF Downloads 113
111 Smart Lean Manufacturing in the Context of Industry 4.0: A Case Study

Authors: M. Ramadan, B. Salah

Abstract:

This paper introduces a framework to digitalize lean manufacturing tools to enhance smart lean-based manufacturing environments or Lean 4.0 manufacturing systems. The paper discusses the integration between lean tools and the powerful features of recent real-time data capturing systems with the help of Information and Communication Technologies (ICT) to develop an intelligent real-time monitoring and controlling system of production operations concerning lean targets. This integration is represented in the Lean 4.0 system called Dynamic Value Stream Mapping (DVSM). Moreover, the paper introduces the practice of Radio Frequency Identification (RFID) and ICT to smartly support lean tools and practices during daily production runs to keep the lean system alive and effective. This work introduces a practical description of how the lean method tools 5S, standardized work, and poka-yoke can be digitalized and smartly monitored and controlled through DVSM. A framework of the three tools has been discussed and put into practice in a German switchgear manufacturer.

Keywords: lean manufacturing, Industry 4.0, radio frequency identification, value stream mapping

Procedia PDF Downloads 201
110 The FINDRISC Score for Prediabetes and Diabetes Screening in Adult Libyan Males

Authors: Issam M Hajjaji, Adel Tajoury, Salah R Benhamid

Abstract:

The MENA region has the highest prevalence of diabetes in the world. Various risk scores were developed, not all appropriate locally. The objective of this study is to apply the FINDRISC Score to adult Libyan males to determine its significance, sensitivity, specificity and Positive Predictive Values as an initial screening tool for type 2 diabetes, and suggest a cut-off point. Methods: 600 subjects answered the questionnaire at their place of work, and their waist, weight, height & BP were measured. Thereafter, after excluding those with known diabetes, an Oral Glucose Tolerance Test was done. Results: 414 subjects aged 19-78 completed the questionnaire and tests. 35 (8.4%) had impaired glucose tolerance (IGT) and 13 (3.1%) had diabetes (DM). The AUC-ROC for IGT was 0.614 (95% CI: 0.527-0.701), for DM 0.810 (95% CI: 0.709-0.911) and for both 0.689 (95% CI: 0.609-0.769). The Positive Predictive Value for a cut-off score of 5 were 15.5%, 11.7% & 5.7% for both conditions combined, prediabetes & diabetes respectively. The equivalent values for a cut-off score of 8 were 16.1%, 9.0% & 7.7%. The Negative Predictive Values were uniformly above 90%. Conclusions & Recommendations: The FINDRISC Score had a low predictive value for dysglycaemia in this sample and performed at a level of significance for IGT that is similar to other MENA countries, but did better for DM. A larger sample that included women is suggested, with a view of adjusting the Score to suit the local population.

Keywords: diabetes, FINDRISK, Libya, prediabetes

Procedia PDF Downloads 103
109 Robust Segmentation of Salient Features in Automatic Breast Ultrasound (ABUS) Images

Authors: Lamees Nasser, Yago Diez, Robert Martí, Joan Martí, Ibrahim Sadek

Abstract:

Automated 3D breast ultrasound (ABUS) screening is a novel modality in medical imaging because of its common characteristics shared with other ultrasound modalities in addition to the three orthogonal planes (i.e., axial, sagittal, and coronal) that are useful in analysis of tumors. In the literature, few automatic approaches exist for typical tasks such as segmentation or registration. In this work, we deal with two problems concerning ABUS images: nipple and rib detection. Nipple and ribs are the most visible and salient features in ABUS images. Determining the nipple position plays a key role in some applications for example evaluation of registration results or lesion follow-up. We present a nipple detection algorithm based on color and shape of the nipple, besides an automatic approach to detect the ribs. In point of fact, rib detection is considered as one of the main stages in chest wall segmentation. This approach consists of four steps. First, images are normalized in order to minimize the intensity variability for a given set of regions within the same image or a set of images. Second, the normalized images are smoothed by using anisotropic diffusion filter. Next, the ribs are detected in each slice by analyzing the eigenvalues of the 3D Hessian matrix. Finally, a breast mask and a probability map of regions detected as ribs are used to remove false positives (FP). Qualitative and quantitative evaluation obtained from a total of 22 cases is performed. For all cases, the average and standard deviation of the root mean square error (RMSE) between manually annotated points placed on the rib surface and detected points on rib borders are 15.1188 mm and 14.7184 mm respectively.

Keywords: Automated 3D Breast Ultrasound, Eigenvalues of Hessian matrix, Nipple detection, Rib detection

Procedia PDF Downloads 305
108 The Ameliorative Effects of the Histamine H3 Receptor Antagonist/Inverse Agonist DL77 on MK801-Induced Memory Deficits in Rats

Authors: B. Sadek, N. Khan, Shreesh K. Ojha, Adel Sadeq, D. Lazewska, K. Kiec-Kononowicz

Abstract:

The involvement of Histamine H3 receptors (H3Rs) in memory and the potential role of H3R antagonists in pharmacological control of neurodegenerative disorders, e.g., Alzheimer disease (AD) is well established. Therefore, the memory-enhancing effects of the H3R antagonist DL77 on MK801-induced cognitive deficits were evaluated in passive avoidance paradigm (PAP) and novel object recognition (NOR) tasks in adult male rats, applying donepezil (DOZ) as a reference drug. Animals pretreated with acute systemic administration of DL77 (2.5, 5, and 10 mg/kg, i.p.) were significantly ameliorated in regard to MK801-induced memory deficits in PAP. The ameliorative effect of most effective dose of DL77 (5 mg/kg, i.p.) was abrogated when animals were pretreated with a co-injection with the H3R agonist R-(α)-methylhistamine (RAMH, 10 mg/kg, i.p.). Moreover, and in the NOR paradigm, DL77 (5 mg/kg, i.p.) reversed MK801-induced deficits long-term memory (LTM), and the DL77-provided procognitive effect was comparable to that of reference drug DOZ, and was reversed when animals were co-injected with RAMH (10 mg/kg, i.p.). However, DL77(5 mg/kg, i.p.) failed to alter short-term memory (STM) impairment in NOR test. Furthermore, DL77 (5 mg/kg) failed to induce any alterations of anxiety and locomotor behaviors of animals naive to elevated-plus maze (EPM), indicating that the ameliorative effects observed in PAP or NOR tests were not associated to alterations in emotions or in natural locomotion of tested animals. These results reveal the potential contribution of H3Rs in modulating CNS neurotransmission systems associated with neurodegenerative disorders, e.g., AD.

Keywords: histamine H3 receptor, antagonist, learning and memory, Alzheimer's disease, neurodegeneration, passive avoidance paradigm, novel object recognition, behavioral research

Procedia PDF Downloads 131
107 Median-Based Nonparametric Estimation of Returns in Mean-Downside Risk Portfolio Frontier

Authors: H. Ben Salah, A. Gannoun, C. de Peretti, A. Trabelsi

Abstract:

The Downside Risk (DSR) model for portfolio optimisation allows to overcome the drawbacks of the classical mean-variance model concerning the asymetry of returns and the risk perception of investors. This model optimization deals with a positive definite matrix that is endogenous with respect to portfolio weights. This aspect makes the problem far more difficult to handle. For this purpose, Athayde (2001) developped a new recurcive minimization procedure that ensures the convergence to the solution. However, when a finite number of observations is available, the portfolio frontier presents an appearance which is not very smooth. In order to overcome that, Athayde (2003) proposed a mean kernel estimation of the returns, so as to create a smoother portfolio frontier. This technique provides an effect similar to the case in which we had continuous observations. In this paper, taking advantage on the the robustness of the median, we replace the mean estimator in Athayde's model by a nonparametric median estimator of the returns. Then, we give a new version of the former algorithm (of Athayde (2001, 2003)). We eventually analyse the properties of this improved portfolio frontier and apply this new method on real examples.

Keywords: Downside Risk, Kernel Method, Median, Nonparametric Estimation, Semivariance

Procedia PDF Downloads 462
106 Fluid Inclusions Analysis of Fluorite from the Hammam Jedidi District, North-Eastern Tunisia

Authors: Miladi Yasmine, Bouhlel Salah, Garnit Hechmi

Abstract:

Hydrothermal vein-type deposits of the Hammam Jedidi F-Ba(Pb-Zn-Cu) are hosted in Lower Jurassic, Cretaceous and Tertiary series, and located near a very important structural lineament (NE-SW) corresponding to the Hammam Jedidi Fault in the Tunisian Dorsale. The circulation of the ore forming fluid is triggered by a regional tectonic compressive phase which occurred during the miocène time. Mineralization occurs as stratabound and vein-type orebodies adjacent to the Triassic salt diapirs and within fault in Jurassic limestone. Fluid inclusions data show that two distinct fluids were involved in the mineralisation deposition: a warmer saline fluid (180°C, 20 wt % NaCl equivalent) and cooler less saline fluid (126°C, 5wt%NaCl equivalent). The contrasting salinities and halogen ratios suggest that this two fluid derived from one of the brine originated after the dissolution of halite as suggested by its high salinity. The other end member, as indicated by the low Cl/Br ratios, acquired its low salinity by dilution of Br enriched evaporated seawater. These results are compatible with Mississippi-Valley- type mineralization.

Keywords: Jebel Oust, fluid inclusions, North Eastern Tunisia, mineralization

Procedia PDF Downloads 317
105 Food and Parasitical Outline on Balls of Raven Corvus corax tingitanus Irby, on 1874 (Aves–Corvidae) in the Public Dump of Oum El Bouaghi (Road of Guelif)

Authors: Faiza Marniche, Amel Milla, Samiha Belmania, Ahlem Fadheli, Salah Eddine Doumandji

Abstract:

Within the public dump of the region of Oum El Bouaghi across the analysis of pellets of réjection which were picked up during two years 2008 and 2009. The diet of Raven Corvus corax tingitanus is studied in relation with available food represented by insects-preys with a parasitical study, on the pellets of this species. The food stored is gotten from the public dump of Oum El Bouaghi during three seasons, we note that insects are predominant during three seasons, autumn (91.62%), winter (58.95%) and springs (77.78%). The analysis of 42 pellets of rejection collected in this station have revealed that insects dominate the diet of Raven through three seasons , the most presented family is that of the Formicidae in autumn (43.5%) and spring (24.2%) however in winter is that of family Carabidae with a percentage of 9.1%. Parasitic analysis on 30 pellets of this species has indicated the existence of three endoparasites, Isospora sp. (Protozoa-Coccidae), Eimeria sp. (Protozoa-Coccidae) and Nematoda sp.ind. (Metazoa-Nemathelmintes).

Keywords: big raven Corvus corax tingitanus, public dump, Oum El Bouaghi, available food, diet, parasites

Procedia PDF Downloads 280
104 Bio-Estimation of Selected Heavy Metals in Shellfish and Their Surrounding Environmental Media

Authors: Ebeed A. Saleh, Kadry M. Sadek, Safaa H. Ghorbal

Abstract:

Due to the determination of the pollution status of fresh resources in the Egyptian territorial waters is very important for public health, this study was carried out to reveal the levels of heavy metals in the shellfish and their environment and its relation to the highly developed industrial activities in those areas. A total of 100 shellfish samples from the Rosetta, Edku, El-Maadiya, Abo-Kir and El-Max coasts [10 crustaceans (shrimp) and 10 mollusks (oysters)] were randomly collected from each coast. Additionally, 10 samples from both the water and the sediment were collected from each coast. Each collected sample was analyzed for cadmium, chromium, copper, lead and zinc residues using a Perkin Elmer atomic absorption spectrophotometer (AAS). The results showed that the levels of heavy metals were higher in the water and sediment from Abo-Kir. The heavy metal levels decreased successively for the Rosetta, Edku, El-Maadiya, and El-Max coasts, and the concentrations of heavy metals, except copper and zinc, in shellfish exhibited the same pattern. For the concentration of heavy metals in shellfish tissue, the highest was zinc and the concentrations decreased successively for copper, lead, chromium and cadmium for all coasts, except the Abo-Kir coast, where the chromium level was highest and the other metals decreased successively for zinc, copper, lead and cadmium. In Rosetta, chromium was higher only in the mollusks, while the level of this metal was lower in the crustaceans; this trend was observed at the Edku, El-Maadiya and El-Max coasts as well. Herein, we discuss the importance of such contamination for public health and the sources of shellfish contamination with heavy metals. We suggest measures to minimize and prevent these pollutants in the aquatic environment and, furthermore, how to protect humans from excessive intake.

Keywords: atomic absorption, heavy metals, sediment, shellfish, water

Procedia PDF Downloads 292
103 Distribution and Comparative Diversity of Nematocera within Four Livestock Types in the Plain of Mitidja Algeria

Authors: Nebri Rachid, Berrouane Fatima, Doumandji Salah Eddine

Abstract:

During six months, from November 2013 to May 2014, census of Nematocera insects was conducted on four livestock: cattle, sheep, equine and cameline. The census, that took place in a station located in Mitidja plain, Algeria, revealed thirteen Nematocera species that had been observed and identified: Scatopse notata, Chironomus Sp., Sciara bicolor, Psychoda phalaenoïdes, Culex pipiens, Orthocladius Sp., Psycoda alternata, Trichocera regelationis, Culicoïdes Sp., Contarinia Sp., Ectaetia Sp., Tipula Sp., and Culicoïdes coprosus. A factorial correspondence analysis has been performed to study the distribution of the different species captured in colored traps that were placed in the four farms. The results showed the presence of three collections of Nematocera relating to the breeding type where the highest availability is in favor of the equine and the cattle. The analysis of the comparative diversity of Nematocera specimens revealed an indifferent taxonomic structure compared with the hosts. However, in terms of individuals, the supremacy is to the equine’s advantage. On the ecological arrival scale, Psycoda alternata, is undeniably the most predominant on the equines as well as on the cattle.

Keywords: Algeria, availability, biodiversity, census, livestock, nematocera

Procedia PDF Downloads 424
102 Utilization of a Composite of Oil Ash, Scoria, and Expanded Perlite with Polyethylene Glycol for Energy Storage Systems

Authors: Khaled Own Mohaisen, Md. Hasan Zahir, Salah U. Al-Dulaijan, Shamsad Ahmad, Mohammed Maslehuddin

Abstract:

Shape-stabilized phase change materials (ss-PCMs) for energy storage systems were developed using perlite, scoria, and oil ash as a carrier, with polyethylene glycol (PEG) with a molecular weight of 6000 as phase change material (PCM). Physical mixing using simple impregnation of ethanol evaporation technique method was carried out to fabricate the form stabilized PCM. The fabricated PCMs prevent leakage, reduce the supercooling effect and minimize recalescence problems of the PCM. The differential scanning calorimetry (DSC) results show that perlite composite (ExPP) has the highest latent heat of melting and freezing values of (141.6 J/g and 143.7 J/g) respectively, compared with oil ash (OAP) and scoria (SCP) composites. Moreover, ExPP has the highest impregnation ratio, energy storage efficiency, and energy storage capacity compared with OAP and SCP. However, OAP and SCP have higher thermal conductivity values compared to ExPP composites which accelerate the thermal storage response in the composite. These results were confirmed with DSC, and the characteristic of the PCMs was investigated by using XRD and FE-SEM techniques.

Keywords: expanded perlite, oil ash, scoria, energy storage material

Procedia PDF Downloads 56
101 Oxidative and Hormonal Disruptions Underlie Bisphenol A: Induced Testicular Toxicity in Male Rabbits

Authors: Kadry M. Sadek, Tarek K. Abouzed, Mousa A. Ayoub

Abstract:

The presence of endocrine-disrupting compounds, such as bisphenol A (BPA), in the environment can cause serious health problems. However, there are controversial opinions. This study investigated the reproductive, metabolic, oxidative and immunologic-disrupting effects of bisphenol A in male rabbits. Rabbits were divided into five groups. The first four rabbit groups were administered oral BPA (1, 10, 50, or 100 mg/kg/day) for ten weeks. The fifth group was administered corn oil as the vehicle. BPA significantly decreased serum testosterone, estradiol and the free androgen index (FAI) and significantly increased sex hormone binding globulin (SHBG) compared with the placebo group. The higher doses of BPA showed a significant decrease in follicular stimulating hormone (FSH) and luteinizing hormone (LH). A significant increase in blood glucose levels was identified in the BPA groups. The non-significant difference in insulin levels is a novel finding. The cumulative testicular toxicity of BPA was clearly demonstrated by the dose-dependent decrease in absolute testes weight, primary measures of semen quality and a significant increase in testicular malonaldehyde (MDA). Moreover, BPA significantly decreased total antioxidant capacity (TAC) and significantly increased immunoglobulin G (IgG) at the highest concentration. Our results suggest that BPA, especially at higher doses, is associated with many adverse effects on metabolism, oxidative stress, immunity, sperm quality and markers of androgenic action. These results may reflect the estrogenic effects of BPA, which we hypothesize could be related, in part, to an inhibitory effect on testicular steroidogenesis. The induction of oxidative stress by BPA may play an additional role in testicular toxicity. These results suggest that BPA poses a threat to endocrine and reproductive functions.

Keywords: bisphenol A, oxidative stress, rabbits, semen quality, steroidogenesis

Procedia PDF Downloads 268
100 Synthesis, Characterization, Computational Study, Antimicrobial Evaluation, in Vivo Toxicity Study of Manganese (II) and Copper (II) Complexes with Derivative Sulfa-drug

Authors: Afaf Bouchoucha, Karima Si Larbi, Mohamed Amine Bourouaia, Salah.Boulanouar, Safia.Djabbar

Abstract:

The synthesis, characterization and comparative biological study of manganese (II) and copper (II) complexes with an heterocyclic ligand used in pharmaceutical field (Scheme 1), were reported. Two kinds of complexes were obtained with derivative sulfonamide, [M (L)₂ (H₂O)₂].H₂O and [M (L)₂ (Cl)₂]3H₂O. These complexes have been prepared and characterized by elemental analysis, FAB mass, ESR magnetic measurements, FTIR, UV-Visible spectra and conductivity. Their stability constants have been determined by potentiometric methods in a water-ethanol (90:10 v/v) mixture at a 0.2 mol l-1 ionic strength (NaCl) and at 25.0 ± 0.1 ºC using Sirko program. DFT calculations were done using B3LYP/6-31G(d) and B3LYP/LanL2DZ. The antimicrobial activity of ligand and complexes against the species Escherichia coli, P. aeruginosa, Klebsiella pneumoniae, S. aureus, Bacillus subtilisan, Candida albicans, Candida tropicalis, Saccharomyces, Aspergillus fumigatus and Aspergillus terreus has been carried out and compared using agar-diffusion method. Also, the toxicity study was evaluated on synchesis complexes using Mice of NMRI strain.

Keywords: hetterocyclic ligand, complex, stability constant, antimicrobial activity, DFT, acute and genotoxicity study

Procedia PDF Downloads 90
99 A New Approach of Preprocessing with SVM Optimization Based on PSO for Bearing Fault Diagnosis

Authors: Tawfik Thelaidjia, Salah Chenikher

Abstract:

Bearing fault diagnosis has attracted significant attention over the past few decades. It consists of two major parts: vibration signal feature extraction and condition classification for the extracted features. In this paper, feature extraction from faulty bearing vibration signals is performed by a combination of the signal’s Kurtosis and features obtained through the preprocessing of the vibration signal samples using Db2 discrete wavelet transform at the fifth level of decomposition. In this way, a 7-dimensional vector of the vibration signal feature is obtained. After feature extraction from vibration signal, the support vector machine (SVM) was applied to automate the fault diagnosis procedure. To improve the classification accuracy for bearing fault prediction, particle swarm optimization (PSO) is employed to simultaneously optimize the SVM kernel function parameter and the penalty parameter. The results have shown feasibility and effectiveness of the proposed approach

Keywords: condition monitoring, discrete wavelet transform, fault diagnosis, kurtosis, machine learning, particle swarm optimization, roller bearing, rotating machines, support vector machine, vibration measurement

Procedia PDF Downloads 412
98 The Impact of Voluntary Disclosure Level on the Cost of Equity Capital in Tunisian's Listed Firms

Authors: Nouha Ben Salah, Mohamed Ali Omri

Abstract:

This paper treats the association between disclosure level and the cost of equity capital in Tunisian’slisted firms. This relation is tested by using two models. The first is used for testing this relation directly by regressing firm specific estimates of cost of equity capital on market beta, firm size and a measure of disclosure level. The second model is used for testing this relation by introducing information asymmetry as mediator variable. This model is suggested by Baron and Kenny (1986) to demonstrate the role of mediator variable in general. Based on a sample of 21 non-financial Tunisian’s listed firms over a period from 2000 to 2004, the results prove that greater disclosure is associated with a lower cost of equity capital. However, the results of indirect relationship indicate a significant positive association between the level of voluntary disclosure and information asymmetry and a significant negative association between information asymmetry and cost of equity capital in contradiction with our previsions. Perhaps this result is due to the biases of measure of information asymmetry.

Keywords: cost of equity capital, voluntary disclosure, information asymmetry, and Tunisian’s listed non-financial firms

Procedia PDF Downloads 491
97 Limitation of Parallel Flow in Three-Dimensional Elongated Porous Domain Subjected to Cross Heat and Mass Flux

Authors: Najwa Mimouni, Omar Rahli, Rachid Bennacer, Salah Chikh

Abstract:

In the present work 2D and 3D numerical simulations of double diffusion natural convection in an elongated enclosure filled with a binary fluid saturating a porous medium are carried out. In the formulation of the problem, the Boussinesq approximation is considered and cross Neumann boundary conditions are specified for heat and mass walls conditions. The numerical method is based on the control volume approach with the third order QUICK scheme. Full approximation storage (FAS) with full multigrid (FMG) method is used to solve the problem. For the explored large range of the controlling parameters, we clearly evidenced that the increase in the depth of the cavity i.e. the lateral aspect ratio has an important effect on the flow patterns. The 2D perfect parallel flows obtained for a small lateral aspect ratio are drastically destabilized by increasing the cavity lateral dimension. This yields a 3D fluid motion with a much more complicated flow pattern and the classically studied 2D parallel flows are impossible.

Keywords: bifurcation, natural convection, heat and mass transfer, parallel flow, porous media

Procedia PDF Downloads 449
96 Reliability of Diffusion Tensor Imaging in Differentiation of Salivary Gland Tumors

Authors: Sally Salah El Menshawy, Ghada M. Ahmed GabAllah, Doaa Khedr M. Khedr

Abstract:

Background: Our study aims to detect the diagnostic role of DTI in the differentiation of salivary glands benign and malignant lesions. Results: Our study included 50 patients (25males and 25 females) divided into 4 groups (benign lesions n=20, malignant tumors n=13, post-operative changes n=10 and normal n=7). 28 patients were with parotid gland lesions, 4 patients were with submandibular gland lesions and only 1 case with sublingual gland affection. The mean fractional anisotropy (FA) and apparent diffusion coefficient (ADC) of malignant salivary gland tumors (n = 13) (0.380±0.082 and 0.877±0.234× 10⁻³ mm² s⁻¹) were significantly different (P<0.001) than that of benign tumors (n = 20) (0.147±0.03 and 1.47±0.605 × 10⁻³ mm² s⁻¹), respectively. The mean FA and ADC of post-operative changes (n = 10) were (0.211±0.069 and 1.63±0.20× 10⁻³ mm² s⁻¹) while that of normal glands (n =7) was (0.251±0.034and 1.54±0.29× 10⁻³ mm² s⁻¹), respectively. Using ADC to differentiate malignant lesions from benign lesions has an (AUC) of 0.810, with an accuracy of 69.7%. ADC used to differentiate malignant lesions from post-operative changes has (AUC) of 1.0, and an accuracy of 95.7%. FA used to discriminate malignant from benign lesions has (AUC) of 1.0, and an accuracy of 93.9%. FA used to differentiate malignant from post-operative changes has (AUC) of 0.923, and an accuracy of 95.7%. Combined FA and ADC used to differentiate malignant from benign lesions has (AUC) of 1.0, and an accuracy of 100%. Combined FA and ADC used to differentiate malignant from post-operative changes has (AUC) of 1.0, and an accuracy of 100%. Conclusion: Combined FA and ADC can differentiate malignant tumors from benign salivary gland lesions.

Keywords: diffusion tensor imaging, MRI, salivary gland, tumors

Procedia PDF Downloads 82
95 Traditional Ceramics Value in the Middle East

Authors: Abdelmessih Malak Sadek Labib

Abstract:

The Stability in harsh environments thanks to excellent electrical, mechanical and thermal properties is what ceramics are all about selected materials for many applications despite advent of new materials such as plastics and composites. However, ceramic materials have disadvantages, including brittleness. Fragility is often attributed to pottery strong covalent and ionic bonds in the ceramic body. There is still much to learn about brittle cracks in a attention to detail, hence the fragility of the ceramic and its catastrophic failure of a frequently studied topic, particularly in charging applications. One of the most commonly used ceramics for load-bearing applications such as veneers is porcelain. Porcelain is a type of traditional pottery. Traditional pottery consists mainly of three basic ingredients: clay, which gives plasticity; silica which maintains the shape and stability of the ceramic body over temperature high temperature; and feldspar affecting glazing. In traditional pottery, the inversion of quartz during cooling the process can create microcracks that act as a stress concentration centers. Consequently, subcritical crack growth is caused due to quartz inversion origins unpredictable catastrophic failure of the work of ceramic bodies when reloading. In the case of porcelain, however, this is what the mullite hypothesis says the strength of porcelain can be significantly increased with felt Interlocking of mullite needles in the ceramic body.in this way realistic assessment of the role of quartz and mullite Porcelain with a strength of is needed to grow stronger and smaller fragile porcelain. Currently,the lack of reports on Young's moduli in the literature leads to erroneous conclusions in this regard mechanical behavior of porcelain. Therefore, the current project uses the Young's modulus approach for the investigation the role of quartz and mullite on the mechanical strength of various porcelains, in addition to reducing particle size, flexural strength fractographic forces and techniques.

Keywords: materials, technical, ceramics, properties, thermal, stability, advantages

Procedia PDF Downloads 59
94 Influence of Vegetable Oil-Based Controlled Cutting Fluid Impinging Supply System on Micro Hardness in Machining of Ti-6Al-4V

Authors: Salah Gariani, Islam Shyha, Fawad Inam, Dehong Huo

Abstract:

A controlled cutting fluid impinging supply system (CUT-LIST) was developed to deliver an accurate amount of cutting fluid into the machining zone via well-positioned coherent nozzles based on a calculation of the heat generated. The performance of the CUT-LIST was evaluated against a conventional flood cutting fluid supply system during step shoulder milling of Ti-6Al-4V using vegetable oil-based cutting fluid. In this paper, the micro-hardness of the machined surface was used as the main criterion to compare the two systems. CUT-LIST provided significant reductions in cutting fluid consumption (up to 42%). Both systems caused increased micro-hardness value at 100 µm from the machined surface, whereas a slight reduction in micro-hardness of 4.5% was measured when using CUL-LIST. It was noted that the first 50 µm is the soft sub-surface promoted by thermal softening, whereas down to 100 µm is the hard sub-surface caused by the cyclic internal work hardening and then gradually decreased until it reached the base material nominal hardness. It can be concluded that the CUT-LIST has always given lower micro-hardness values near the machined surfaces in all conditions investigated.

Keywords: impinging supply system, micro-hardness, shoulder milling, Ti-6Al-4V, vegetable oil-based cutting fluid

Procedia PDF Downloads 261
93 DNA Polymorphism Studies of β-Lactoglobulin Gene in Native Saudi Goat Breeds

Authors: Amr A. El Hanafy, Muhammad I. Qureshi, Jamal Sabir, Mohamed Mutawakil, Mohamed M. Ahmed, Hassan El Ashmaoui, Hassan Ramadan, Mohamed Abou-Alsoud, Mahmoud Abdel Sadek

Abstract:

β-Lactoglobulin (β-LG) is the dominant non-casein whey protein found in bovine milk and of most ruminants. The amino acid sequence of β-LG along with its 3-dimensional structure illustrates linkage with the lipocalin superfamily. Preliminary studies in goats indicated that milk yield can be influenced by polymorphism in genes coding for whey proteins. The aim of this study is to identify and evaluate the incidence of functional polymorphisms in the exonic and intronic portions of β-LG gene in native Saudi goat breeds (Ardi, Habsi, and Harri). Blood samples were collected from 300 animals (100 for each breed) and genomic DNA was extracted using QIAamp DNA extraction Kit. A fragment of the β-LG gene from exon 7 to 3’ flanking region was amplified with pairs of specific primers. Subsequent digestion with Sac II restriction endonuclease revealed two alleles (A and B) and three different banding patterns or genotypes i.e. AA, AB and BB. The statistical analysis showed that β-LG AA genotype had higher milk yield than β-LG AB and β-LG BB genotypes. Nucleotide sequencing of the selected β-LG fragments was done and submitted to GenBank NCBI (Accession No. KJ544248, KJ588275, KJ588276, KJ783455, KJ783456 and KJ874959). Two already established SNPs in exon 7 (+4601 and +4603) and one fresh SNP in the 3’ UTR region were detected in the β-LG fragments with designated AA genotype. The polymorphisms in exon 7 did not produce any amino acid change. Phylogenetic analysis on the basis of nucleotide sequences of native Saudi goats indicated evolutional similarity with the GenBank reference sequences of goat, Bubalus bubalis and Bos taurus.

Keywords: β-Lactoglobulin, Saudi goats, PCR-RFLP, functional polymorphism, nucleotide sequencing, phylogenetic analysis

Procedia PDF Downloads 465
92 Carbon Monoxide Poisoning in Children

Authors: Atitallah Sofien, Bouyahia Olfa, Hadj Salah Ibrahim, Ben Saleh Foued, Missaoui Nada, Ben Rabeh Rania, Yahyaoui Salem, Mazigh Sonia, Boukthir Samir

Abstract:

Introduction: Carbon monoxide (CO) poisoning is a common pathology responsible for high morbidity and mortality worldwide. Aim: The purpose of this study was to determine the epidemiological profile of CO poisoning as well as its clinical, paraclinical, therapeutic, and evolutionary aspects. Methods: Our study included observations of CO poisoning in children hospitalized in the pediatric department C of the Children's Hospital in Tunis over a period of 3 years. Results: We have collected 199 cases of CO poisoning in children. The average age was 5.43 years, with a sex ratio of 0.98. The source of CO was inside the home in 73.2% of cases, and it was the gas bath heater in 68.8% of cases. The intoxication was collective in 93.5% of the cases, and it occurred during the month of January in 35.8% of the cases. The clinical manifestations were headaches in 69.5% of cases. The rate of carboxyhemoglobin was pathological in 73.9% of cases. All patients received normobaric oxygen therapy, and only 3.6% of patients had a hyperbaric oxygen therapy session. We did not deplore any case of death in our study. Conclusion: CO poisoning remains a public health problem in Tunisia with high morbidity. The risk of secondary complications, particularly neuropsychiatric, requires clinical and possibly neuroradiological monitoring of these victims.

Keywords: poisoning, carbon monoxide, children, hyperbaric oxygenation

Procedia PDF Downloads 40
91 The Mechanism of Antimicrobial Activity and Antioxidant Effects of the Essential Oil and the Methanolic Extract of Carum montanum (Coss. et Dur.) Benth. Et Hook. Aerial Parts from Algeria

Authors: Meriem El Kolli, Hocine Laouer, Hayet El Kolli, Salah Akkal

Abstract:

The methanolic extract (ME) of C. montanum obtained by a hydo-alcoholic maceration and its polyphenol content was evaluated by Folin-Ciocalteu method. This extract and C. montanum essential oil were screened for antimicrobial activity against 21 microbial strains by agar diffusion method. MICs of the EO were determined by the broth micro dilution method. The mechanism of action of the EO was determined on the susceptible strains by the time kill assay and the lysis experience. Antioxidant properties were studied by both free DPPH radical scavenging and reducing power techniques. The TPC in the ME showed a high level of 101.50 ± 5.33 mg GAE /mg. B. cereus was the most sensitive strain with MIC of 55.5 µg/ml , then K. pneumoniae (111 µg/ml). A remarkable decrease in a survival rate as well as in the absorbance at 260 nm were recorded, which suggest that the cytoplasm membrane is one of the targets of the EO. Antioxidant effects were concentration dependent and IC50 values were 1.09 ± 0.37 µg/ml for the EO and 65.04 ± 0.00 µg/ml for the ME by DPPH method and a reducing power dose-dependent. In conclusion, C. montanum extracts showed potent which could be exploited in the food industry for food preservation.

Keywords: C. montanum, Apiaceae, essential oils, antimicrobial activity, antioxidant activity, reducing power

Procedia PDF Downloads 211
90 Moroccan Human Ecological Behavior: Grounded Theory Approach

Authors: Dalal Tarfaoui, Salah Zkim

Abstract:

Today, environmental sustainability is everyone’s concern as it contributes in many aspects to a country's development. Morocco is also aware of the increasing threats to its natural resources. Accordingly, many projects and research have been discussed pointing mainly to water security, pollution, desertification, and land degradation, but few studies bothered to dig into the human demeanor to disclose its ecological behavior. Human behavior is accountable for environment deterioration in the first place, but we keep fighting the symptoms instead of limiting the root causes. In the conceptual framework highlighted in the present article, semi-structured interviews have been conducted using a grounded theory approach. Initially this study will serve as a pilot study and a cornerstone to approve a bigger project now in progress. Beyond the existing general ecological measures (GEM), this study has chosen the grounded theory approach to bring out firsthand insights, and probe to which extent an ecological dimension exists in Morocco as a developing country. The discourse of the ecological behavior within the Moroccan context is seen in more realist, social, and community philosophy. The study has revealed an appreciative ecological behavior that is unfortunately repressed by variables beyond people’s control, which would prevent the people’s environmental good intentions to be translated into real ecological actions.

Keywords: ecological behavior, ecological dimension, variables beyond people’s control, Morocco

Procedia PDF Downloads 464
89 Mineralisation and Fluid Inclusions Studies of the Fluorite Deposit at Jebel Mecella, North Eastern Tunisia

Authors: Miladi Yasmine, Bouhlel Salah, Garnit Hechmi, David Banks

Abstract:

The Jebel Mecella F (Ba-Pb-Zn) ore deposits of the Zaghouan district are located in northeastern Tunisia, 60 km south of Tunis. The host rocks belong to the Ressas Formation of Kimmeridgian-Tithonian age and lower Cretaceous layers. Mineralisations occur as stratiform lenses and fracture fillings. The ore mineral assemblage is composed of fluorite, barite, sphalerite galena, and quartz. Primary fluid inclusions in sphalerite have homogenization temperatures ranging from 129 to 145°C final melting temperature range from -14.9 to -10.0, corresponding to salinities of 14.0 to 17.7 wt% NaCl equivalent. Fluid inclusions in fluorite homogenize to the liquid phase between 116 and 160°C. The final ice melting temperature ranges from -23 to -15 °C, corresponding to salinities between 17 and 24 wt% NaCl equivalent. The LAICP-MS analyses of the fluid inclusions in fluorite show that these fluids are dominated by Na>K>Mg. Furthermore, the high K/Na values from fluid inclusions suggest the brine interacted with K-rich rocks in the basement or in siliciclastic sediments in the basins. The ore fluids in Jebel Mecella are highly saline and Na-K dominated with lower Mg concentrations, and come from the leaching of the dolomitic host rocks. These results are compatible with Mississippi-Valley-type mineralizing fluids.

Keywords: Jebel Mecella, fluid inclusions, micro thermometry, LA-ICP-MS

Procedia PDF Downloads 169
88 Impact of Two Herbal Seeds Supplementation on Growth Performance and Some Biochemical Blood and Tissue Parameters of Broiler Chickens

Authors: Hamada A. Ahmed, Kadry M. Sadek, Ayman E. Taha

Abstract:

The effects of basil and/or chamomile seed supplementation on the growth of Hubbard broiler chicks were evaluated. The antioxidant effects of these supplements were also assessed. One hundred and twenty 1-day-old broiler chicks were randomly divided into four equal groups. The control group (group 1) was fed a basal diet (BD) without supplementation. Groups 2, 3, and 4 were fed the BD supplemented with 10g basil, 10g chamomile, and 5g basil plus 5g chamomile per kg of food, respectively. Basil supplementation alone or in combination with chamomile non-significantly (P≥0.05) increased final body weight (3.2% and 0.3%, respectively) and weight gain (3.5% and 3.6%, respectively) over the experimental period. Chamomile supplementation alone non-significantly (P≥0.05) reduced final body weight and weight gain over the experimental period by 1.7% and 1.7%, respectively. In comparison to the control group, herbal seed supplementation reduced feed intake and improved the feed conversion and protein efficiency ratios. In general, basil seed supplementation stimulated chicken growth and improved the feed efficiency more effectively than chamomile seed supplementation. The antioxidant activities of basil and/or chamomile supplementation were examined in the thymus, bursa, and spleen. In chickens that received supplements, the level of malondialdehyde was significantly decreased, whereas the activities of glutathione, superoxide dismutase, and catalase were significantly increased (P<0.05). Supplementation of basil and/or chamomile did not affect blood protein levels, but had lipid-lowering effects as evidenced by reduced serum levels of total lipids, triglycerides, and cholesterol. In conclusion, supplementation of basil and/or chamomile improved growth parameters in broiler chicks and had antioxidant and blood lipid-lowering effects. These beneficial effects of basil and/or chamomile supplementation resulted in economically viable production of high-quality white meat containing no harmful residues.

Keywords: herbal additives, basil, chamomile, broiler, growth performance, antioxidant

Procedia PDF Downloads 519
87 Pricing European Options under Jump Diffusion Models with Fast L-stable Padé Scheme

Authors: Salah Alrabeei, Mohammad Yousuf

Abstract:

The goal of option pricing theory is to help the investors to manage their money, enhance returns and control their financial future by theoretically valuing their options. Modeling option pricing by Black-School models with jumps guarantees to consider the market movement. However, only numerical methods can solve this model. Furthermore, not all the numerical methods are efficient to solve these models because they have nonsmoothing payoffs or discontinuous derivatives at the exercise price. In this paper, the exponential time differencing (ETD) method is applied for solving partial integrodifferential equations arising in pricing European options under Merton’s and Kou’s jump-diffusion models. Fast Fourier Transform (FFT) algorithm is used as a matrix-vector multiplication solver, which reduces the complexity from O(M2) into O(M logM). A partial fraction form of Pad`e schemes is used to overcome the complexity of inverting polynomial of matrices. These two tools guarantee to get efficient and accurate numerical solutions. We construct a parallel and easy to implement a version of the numerical scheme. Numerical experiments are given to show how fast and accurate is our scheme.

Keywords: Integral differential equations, , L-stable methods, pricing European options, Jump–diffusion model

Procedia PDF Downloads 123
86 The Effect of Supplementary Cementitious Materials on Fresh and Hardened Properties of Self-Compacting Concretes

Authors: Akram Salah Eddine Belaidi, Said Kenai, El-Hadj Kadri, Benchaâ Benabed, Hamza Soualhi

Abstract:

Self-compacting concrete (SCC) was developed in the middle of the 1980’s in Japan. SCC flows alone under its dead weight and consolidates itself without any entry of additional compaction energy and without segregation. As an integral part of a SCC, self-compacting mortars (SCM) may serve as a basis for the mix design of concrete since the measurement of the rheological properties of SCCs. This paper discusses the effect of using natural pozzolana (PZ) and marble powder (MP) in two alternative systems ratios PZ/MP = 1 and 1/3 of the performance of the SCC. A total of 11 SCC’s were prepared having a constant water-binder (w/b) ratio of 0.40 and total cementitious materials content of 475 kg/m3. Then, the fresh properties of the mortars were tested for mini-slump flow diameter and mini-V-funnel flow time for SCMs and Slumps flow test, L-Box height ratio, V-Funnel flow time and sieve stability for SCC. Moreover, the development in the compressive strength was determined at 3, 7, 28, 56, and 90 days. Test results have shown that using of ternary blends improved the fresh properties of the mixtures. The compressive strength of SCC at 90 days with 30% of PZ and MP was similar to those of ordinary concrete use in situ.

Keywords: self-compacting mortar, self-compacting concrete, natural pozzolana, marble powder, rheology, compressive strength

Procedia PDF Downloads 349