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Search Results: 1 - 10 of 5254 matches for " Bernard Zouma "
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External Magnetic Field Effect on Bifacial Silicon Solar Cell’s Electrical Parameters  [PDF]
Issa Zerbo, Martial Zoungrana, Idrissa Sourabié, Adama Ouedraogo, Bernard Zouma, Dieudonné Joseph Bathiebo
Energy and Power Engineering (EPE) , 2016, DOI: 10.4236/epe.2016.83013
Abstract: The aim of this work is to present a theoretical study of external magnetic field effect on a bifacial silicon solar cell’s electrical parameters (peak power, fill factor and load resistance) using the J-V and P-V characteristics. After the resolution of the magneto transport equation and continuity equation of excess minority carriers in the base of the bifacial silicon solar cell under multispectral illumination, the photo-current density and the photovoltage are determined and the J-V and P-V curves are plotted. Using simultaneously the J-V and P-V curves, we determine, according to magnetic field intensity, the peak photocurrent density, the peak photovoltage, the peak electric power, the fill factor and the load resistance at the peak power point. The numerical data show that the solar cell’s peak power decreases with magnetic field intensity while the fill factor and the load resistance increase.
3D study to improve the IQE of the bifacial polycrystalline silicon solar cell from the grain’s geometries and the applied magnetic field
MOMAR DIAW,Bernard Zouma,AHMETH SERE,Senghane Mbodji
International Journal of Engineering Science and Technology , 2012,
Abstract: A study aiming to an improved internal quantum efficiency of silicon solar cell is presented. The efficiency depends on several internal and external parameters. Especially the polycrystalline silicon solar cell, which is the most used for the terrestrial applications of photovoltaic solar energy, has the lowest efficiency. Because there are many grains and grain boundaries with much recombination of the carriers at the grain boundaries, thus the structure of the grain as its geometry becomes an internal key parameter for this efficiency.The external key parameter taken into account here is the magnetic field. Although its effect on the carriers is well known, its impact on the recombination’s phenomena into the two different regions of the cell like the emitter and the base needs to be known. Before doing it, two classical geometries of the grain are retained toinvestigate through simulation an adequate structure providing a high efficiency. Thus an appropriated 3D model with new assumptions is used to describe the bifacial polycrystalline silicon solar cell and new expressions of carrier densities, photocurrent and quantum efficiency are established.
Experimental study of shea butter extraction efficiency using a centrifugal process
zouma Coulibaly,Stéphane Ouédraogo,Nathalie Niculescu
Journal of Engineering and Applied Sciences , 2009,
Abstract: The experiments carried out focused on shea butter extraction with a centrifuge machine. Experiments were carried out in the laboratory with a small centrifuge, with a view to determining how parameters such as kernel paste temperature, dilution rate and centrifugation speed affected extraction efficiency. High efficiencies (over 30%) were obtained with accelerations over 1,293 g, a kernel paste temperature over 90°C and dilution over 50%. The centrifuge machine that had been designed was then tested using the same variables as parameters for butter extraction efficiency at various sites. Extraction efficiency was found to be barely higher than 30% on average. Mean efficiency values with traditional methods were found to be virtually the same as for the centrifugal process.
E. SOW,S. MBODJI,B. Zouma,M. Zoungrana
International Journal of Science, Environment and Technology , 2012,
New Formulas for Irregular Sampling of Two-Bands Signals  [PDF]
Bernard Lacaze
Journal of Signal and Information Processing (JSIP) , 2011, DOI: 10.4236/jsip.2011.24035
Abstract: Many sampling formulas are available for processes in baseband (-a,a) at the Nyquist rate a/π. However signals of telecommunications have power spectra which occupate two bands or more. We know that PNS (periodic non-uniform sampling) allow an errorless reconstruction at rate smaller than the Nyquist one. For instance PNS2 can be used in the two-bands case (-a,-b)∪(b,a) at the Landau rate (a-b)/π We prove a set of formulas which are available in cases more general than the PNS2. They take into account two sampling sequences which can be periodic or not and with same mean rate or not.
Pairing Effect on the Binding Energy Curve of N = Z Atomic Nuclei  [PDF]
Bernard Schaeffer
World Journal of Nuclear Science and Technology (WJNST) , 2013, DOI: 10.4236/wjnst.2013.33013

The saw-tooth phenomenon on the binding energy curve of N = Z nuclei is due to the low binding energy between the α-particles. It was suspected by Gamow to be of van der Waals type, found here to be deuteron bonds. The binding energy per nucleon, in absolute value, of an α-particle is larger than any other combination of 4 nucleons. Therefore, the binding energy per nucleon is low for odd-odd N = Z nuclei and maximum for even-even N = Z nuclei. The assumption of N = Z nuclei to be an assembly of α-particles and deuteron bonds predicts the binding energy of the 32 first N = Z nuclei with a rms deviation of 0.25 MeV.

Magic of Language  [PDF]
Bernard Korzeniewski
Open Journal of Philosophy (OJPP) , 2013, DOI: 10.4236/ojpp.2013.34067
Abstract: Language, through the discrete nature of linguistic names and strictly determined grammatical rules, creates absolute, “quantized”, sharply separated “facts” within the external world that is continuous, “fuzzy” and relational in its essence. Therefore, it is similar, in some important sense, to magic, which attributes causal and creative power to magical words and formulas. On the one hand, language increases greatly the effectiveness of the processes of thinking and interpersonal communication, yet, on the other hand, it determines and distorts to a large extent the picture of the world created within the mind. The relatively smallest (but still significant) magical admixture is present in science, because of its relatively reliable methodology, while the largest is found in religion and a large part of philosophy. The magical nature of language also manifests itself in logic and mathematics that refer to ill determined, fuzzy objects, sets and relations in the real world. The meaning of linguistic names is based on the conceptual network—an epiphenomenon (continuous in its essence) of the neural network—where interactions between particular concepts are based on the relation of connotation. The names and formulas of language correspond to these concepts which are best separated and determined. A direct relation of denotation between the elements of language and “facts” of the world is an illusion. While we cannot dispense with language because of its immense usefulness, we must remember about its “fact-creating” nature and influence on our thought and cognitive processes. The picture of the reality created as the result of them is to a large extent formed and deformed by the nature of language, and not by the “immanent” properties of the world in itself.
Formal Similarities between Cybernetic Definition of Life and Cybernetic Model of Self-Consciousness: Universal Definition/Model of Individual  [PDF]
Bernard Korzeniewski
Open Journal of Philosophy (OJPP) , 2013, DOI: 10.4236/ojpp.2013.32049
Abstract: The previously proposed cybernetic definition of a living (biological) individual and the cybernetic model of a psychical individual (a self endowed with subjective consciousness) are extended and compared, and their formal similarities are isolated and highlighted. It is argued that the emergence of the biological level of reality from the physical level and of the psychical level from the biological level is closely analogous. The (biological or psychical) individual is constituted by a network of elements (negative feedbacks/ regulatory mechanisms or neurons/concepts, respectively) that possesses the following common properties: 1) it is intentional (in the operational sense); 2) its elements signify (have sense) by connotation (through relations to each other); 3) it contains an instrumental representation of (some aspects of) the world and 4) it is self-referential i.e. recurrently directed on itself (its own reproduction or representation, respectively). Thus life and self-consciousness have deep, formal, structural similarities when viewed abstractly. The cybernetic definition/model of an individual is also referred to societies/states, companies and other systems. It is postulated that this definition/model is a universal one and can be applied to all possible systems/objects existing in the Universe or constructed in the future by humans.
IUPAC Periodic Table Quantum Mechanics Consistent  [PDF]
Bernard Schaeffer
Journal of Modern Physics (JMP) , 2014, DOI: 10.4236/jmp.2014.53020

Most periodic tables of the chemical elements are between 96% and 100% in accord with quantum mechanics. Three elements only do not fit correctly into the official tables, in disagreement with the spherical harmonics and the Pauli exclusion principle. Helium, belonging to the s-block, should be placed beside hydrogen in the s-block instead of the p-block. Lutetium and lawrencium belonging to the d-block of the transition metals should not be in the f-block of the lanthanides or the actinoids. With these slight modifications, the IUPAC table becomes quantum mechanics consistent.

Assessing the quality of the management skills required for lower respiratory tract infections in Kilimanjaro, Tanzania  [PDF]
Bernard Mbwele
Health (Health) , 2014, DOI: 10.4236/health.2014.61004
Abstract: Background: Lower respiratory tract infections (LRTI) are among the leading causes of morbidity and mortality. A severe form of atypical pneumonia, Q fever, has been found in Northern Tanzania. Assessment of the quality of health care for lower respiratory tract infection from the clinicians’ performance has rarely been performed. Methods: A cross sectional descriptive study using the qualitative and quantitative approaches for assessing clinicians and patient files from 11 health facilities of Kilimanjaro region. The facilities were of 4 different levels of public health care delivery and 1 private independent hospital. Results: Medications for LRTI were highly variable in 346 files and from attempts of treatment reported in 53 clinician’s interviews. No file showed attempts for assessing the severity of Pneumonia. Only 6 (11.1%) clinicians could mention causes of atypical pneumonia. Only 7 clinicians (13.0%) were aware of Q-fever and could mention the cause. The quality of clinical records for monitoring the progress was not the same in all levels of care and the difference in availability was statistically significant as level of mental state χ2 (4) = 139.4; P value < 0.001, blood pressure χ2 (8) = 75.2; P value < 0.001, temperature χ2 (4) = 78.7; P value < 0.001, pulse rate χ2 (4) = 139.1; P value < 0.001, respiratory rate χ2 (4) = 197.7; P value < 0.001, auscultation χ2 (4) = 92.2; P value < 0.001. Conclusion: National guidelines for LRTI in Tanzania shall include severity assessments and how to rule out atypical pneumonia using evidence base approaches.
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