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Using the density functional theory (DFT) based on full-potential linearized augmented plane wave (FP-LAPW) method, we computed the structural, electronic, and elastic properties of Ru2CrAl Heusler alloy, with L21 cubic structure. We calculated the lattice constants, partial, and total spin magnetic moments within the general gradient approximation method (GGA) and GGA+U (U: Hubbard parameter). Moreover, we applied the modified Becke–Johnson approximation (mBj) to study the electronic characteristics. The calculated densities of states (DOS) of this alloy show a semi-metallic behavior with a real gap at Fermi level (EF) by the GGA and the mBj approximations, whereas where using the GGA+U approach, the Ru2CrAl exhibit a near half metallic with an indirect pseudogap. We also calculated the mechanical properties using the Charpin model integrated in the Wien2k software. We note that this compound is mechanically stable. The obtained results indicate that this ternary alloy is attractive candidate in spintronic sector.

Bioerosion and encrustation on Pliocene oysters of Lower Chelif basin (NW Algeria).- Two species of oysters (Hyotissa hyotis ; Ostrea lamellosa) have been identified in the Pliocene beds of the lower Chelif basin. They show a heterogeneous distribution between the different levels studied with a random distribution. The shells are almost completely disarticulated and are rarely fragmented. Seven ichnotaxa corresponding to bioerosion structures have been identified (Entobia, Trypanites, Maeandropolydora, Caulostrepsis, Oichnus, Gastrochaenolites and Rogerella), with a dominance of Entobia, Caulostrepsis and Trypanites. Rare traces of encrustation of bivalves and juvenile oysters, barnacles and bryozoans, are observed in particular on the external face of the left valves.The material undergoes multiple reworkings resulting in bio-erosion and bio-encrustation on either side of the valves. Most of the identified ichnotaxa were preserved post-mortem (hence episodes of eroded barnacle encrustations invaded by punctures, notably Entobia), with rare examples of preservation of still-living individuals, represented by Entobia and Caulostrepsis. The settling of oyster levels in both regions indicates a foreshore (estran) environment with medium energy and a short exposure time on the bottom, characterizing a regression phase.

The present work reviews the lithostratigraphy, biostratigraphy, and sedimentology of the Cenomanian–Turonian interval across the Tinrhert Plateau (southeastern Algeria). Five stratigraphic units, previously presented as informal units, are formally defined: the Mazoula (lower–middle Cenomanian), the Bordj Omar Driss (upper Cenomanian–lower Turonian), the In Adaoui (lower Turonian), the Ben Houilet (lower–middle Turonian), and the Takouazet (upper Turonian) formations. The Mazoula Formation consists of gypsiferous marls with a few bioclastic horizons. The Bordj Omar Driss Formation comprises three informal units: (a) the lower limestone unit composed of hard bioclastic limestones containing bivalves (mostly oysters), gastropods, and echinoids, (b) the middle limestone unit consisting of limestone, with an abundance of bivalves, gastropods, echinoids, ammonoids, and benthic foraminifers, (c) the upper limestone unit dominated by fine-grained limestones containing abundant ammonites, planktic foraminifers, and roveacrinids. The In Adaoui Formation is characterized by rich-ammonite limestone beds interbedded with yellowish-greenish marls. The Ben Houilet Formation can be subdivided informally into three units: (a) the mixed siliciclastic-carbonate unit composed of green marls interbedded with sandstones and bioclastic limestones; (b) the marly-limestone unit; (c) the gypsum and red beds unit. The Takouazet Formation is of indurated limestone beds devoid of fossils. The investigated succession is subdivided into four ammonite biozones: the Neolobites vibrayeanus, the Nigericeras gadeni, the Vascoceras cauvini, and the Pseudotissotia nigeriensis-Choffaticeras sinaiticum zones. The Cenomanian–Turonian boundary is located at the limit between the Bordj Omar Driss and In Adaoui Formations, coincident with the base of the Pseudotissotia nigeriensis-Choffaticeras sinaiticum Zone. The studied succession shows the development of a ramp depositional system in response to the early Late Cretaceous second-order sea-level rise at the southern margin of the Tethys. Sequence-stratigraphic surfaces and system tracts are identified and tracked across the Tinrhert Plateau resulting in a detailed reconstruction. Four sedimentary unconformities (SB Tin 1-4) are recognized and tracked laterally, defining three third-order depositional sequences (DS Tin 1-3).

Bu yazıda, her ikisini de kullanan bağımsız bir hibrit güç sistemi önerilmiştir: fotovoltaik jeneratör (PVG) ve Sabit Mıknatıslı Senkron Jeneratör (PMSG), DC veriyoluna bağlı lityum tipi bir batarya ile entegre edilmiştir. Genel sistemin performansının ve güvenilirliğinin iyileştirilmesi garanti edilir. Bu amaçla öncelikle Perturb ve Observe (P&O) yöntemi ve Bulanık Mantık Kontrolü (FLC) yaklaşımı gibi iki MPPT tekniği kullanılarak PVG sisteminin verimliliği arttırılabilir. Evrim, doğal seleksiyon ve genetik mutasyon ilkelerini kullanan Genetik Algoritmalar (ga'lar) daha sonra FLC kazanımlarının ayarlanmasındaki zorlukları ele almak için tanıtılır. Stabilite ve enerji depolama sağlamak için bir lityum-iyon pil modeli sunulmuştur. Ayrıca, pmsg'ye dayalı rüzgar enerjisi dönüşüm sistemi (WECS) modeli sunulmuştur. Bu nedenle, gradyan yöntemiyle kontrol, jeneratörün teslim edilen gücüne ve mekanik hızına dayalı bir MPPT tasarlamaya izin verir. Her iki kaynak da, Uzay Vektör Modülasyonu (SVM) tekniği ile kontrol edilen iki seviyeli bir voltaj kaynağı invertörü vasıtasıyla şebekeye bağlanır. Son olarak, MATLAB / SİMULİNK yazılımı kullanılarak elde edilen simülasyon sonuçları, önerilen kontrolörler kullanıldığında açıkça ortaya çıkan ve bağımsız hibrit sistemin performansına ışık tutan yüksek performansla önerilen kontrol stratejilerinin etkinliğini kanıtlamıştır., In this paper, a stand-alone hybrid power system has been proposed using both: photovoltaic generator (PVG) and permanent magnets synchronous generator (PMSG), integrated with a lithium-type battery connected to the DC bus. The improvement of performance and reliability of the overall system are guaranteed. For this aim, the efficiency of the PVG system can be enhanced firstly by using two MPPT's techniques, such as the Perturb and Observe (P&O) method and the Fuzzy Logic Control (FLC) approach. The Genetic Algorithms (GA’s), using the principles of evolution, natural selection, and genetic mutation, are then introduced to address difficulties in the adjustment of the FLC gains. A lithium-ion battery model is presented to ensure stability and energy storage. Furthermore, the model of the wind energy conversion system (WECS) based on PMSG is presented. Hence, the control by the gradient method, allowing designing an MPPT based on the delivered power and mechanical speed of the generator. Both sources are connected to the grid via a two-level voltage source inverter controlled by Space Vector Modulation (SVM) technique. Finally, simulation results obtained using MATLAB / SIMULINK software proved the effectiveness of proposed control strategies with high performance which is manifested clearly when the suggested controllers employed and shed light on the performance of the stand-alone hybrid system.

Resume Dans la partie sud-est des Monts des Ksour (Algerie), une etude stratigraphique, paleontologique et sedimentologique a ete effectuee sur les couches rouges qui affleurent sur la rive gauche de l’Oued Tafarahit. Il s’agit d’une serie continentale detritique granodecroissante composee de microconglomerats, de gres et d’argiles attribuees au Cenozoique sans preuve paleontologique. Les niveaux argileux ont livre des charophytes [Peckichara atlasensis, Maedleriella cristellata, Nitellopsis (Tectochara) thaleri, Grovesichara sp. et Lamprothamnium papulosum] et des ostracodes (Neocyprideis meguerchiensis, Cyprinotus? sp et Herpetocypris? sp). Cette flore et cette faune permettent d’assigner la Formation Detritique de l’Oued Tafarahit a l’Ypresien inferieur et de confirmer l’existence d’une relation paleobiogeographique etroite entre l’Afrique du Nord et l’Europe du Sud pendant l’Eocene inferieur. La sedimentologie et les microfossiles suggerent un depot dans un environnement fluviatile. Les ostracodes sont typiques des milieux dulcaquicoles a euryhalins. Les formes dulcaquicoles (Cyprinotus? sp. et Herpetocypris? sp.) correspondent probablement a des phases de dessalure lors des periodes de crue. En revanche, l’espece d’eau saumâtre (Neocyprideis meguerchiensis) est caracteristique des phases de salure lors des periodes d’etiage.

The aim of this paper is to convince the non-linearity of conventional systems such as a rectifier-filter-inverter cascade and their most widely used direct conversion techniques which are used to power industrial multi-stator two-phase machines such as the DSIM. It is preferable to replace these systems with a direct and more compact AC/AC converter by three-phases matrix converter, while retaining good input-output waveforms and the possibility of adjusting the input power factor. The Park transformation and the orientation of the IFOC rotor flow can separate the strong coupling between the flux and the torque, in order to have the same performances as those of DC motors. On another hand we design a robust fuzzy logic controller FLC when these inference rules inspired by expertise, which remedy exogenous and endogenous variations such as the parametric variations of the DSIM machine. The performance and efficiency of the proposed FLC strategy used for controlling the three-phases matrix converters associated with the double star induction motor (DSIM) was illustrated by simulation using a Matlab-Simulink.

Environmental decontamination is a major challenge due to the rapid growth of industrial and technological development, requiring an important consumption of fossil energies. Nowadays, a new way to...

In this paper, an experimental study on the effects of the hydraulic diameter on heat transfer and fluid flow characteristics in fully developed turbulent flow in a rectangular channel with one wall (upper) exposed to the heat flux is presented. The hydraulic diameter of the channel was varied by using a wooden block mounted on the bottom wall of the channel. The block to channel height ratio, Hb/H was kept at 0.6, the block to channel length ratio L b /L was kept at 1, and the block to channel width ratio, B b /B was varied from 0 to 0.6. Four cases were investigated in this study for Reynolds number ranging from 6,000 to 20,000. The results of this investigation demonstrate that, the pressure drop is increased with decreasing hydraulic diameter and heat transfer coefficient is decreased with decreasing hydraulic diameter.

Resume Le Cretace superieur de la partie orientale des Monts des Ksour (Atlas saharien, Algerie) est classiquement subdivise en trois formations lithostratigraphiques fossiliferes : El Rhelida (Cenomanien inferieur), Mdaouer (Cenomanien inferieur-moyen) et Rhoundjaia (Cenomanien superieur-Turonien inferieur). La partie occidentale des Monts des Ksour, moins documentee et peu etudiee a ce jour, fait l’objet ici d’une etude sedimentologique et paleontologique detaillee. A Hassi Djeifa (region de Forthassa), le Cretace superieur est represente par la partie superieure de la Formation de Mdaouer puis par la Formation de Rhoundjaia. Les depots attribues a la Formation de Mdaouer sont constitues de marnes rougeâtres ou verdâtres, intercalees de calcaires bio-lamines, de calcaires bioclastiques a gasteropodes et bivalves et de gres. Les niveaux marneux ont livre une faune composee d’ostracodes (Damonella spp., Ilyocypris? sp., Cypridea sp. et Paracypria? sp.), de selaciens (Mafdetia tibniensis et Baharipristis bastetiae) et de pycnodontiformes. Les deux especes de selaciens (Ordre des Rajiformes) n’etaient jusqu’ici connues que du Cenomanien inferieur d’Egypte. Les donnees sedimentologiques et paleontologiques suggerent un âge cenomanien inferieur probable pour les depots etudies et indiquent un paleo-environnement de plaine cotiere continuellement influencee par l’action de marees.

A computational study of heat transfer augmentation in a rectangular channel having rectangular ribs on the upper wall and triangular baffles/fins on the opposite wall by using Computational Fluid Dynamics (CFD) software (ANSYS FLUENT R18.2) is presented in the paper. Effects of Reynolds number on both the flow variables (velocity, pressure, turbulent kinetic energy) and heat transfer variables (temperature and heat transfer coefficient) for three different types of ribs/fins configurations were investigated. The three cases of study are: 1. Ribs Top Smooth Bottom Channel; (RTSBC), 2. Smooth Top Fin Bottom Wall (STFBC) and 3. Ribs Top Fin Bottom Channel (RTFBC). The computation based on finite volume with SIMPLE algorithm have been conducted for air flow in terms of Reynolds number ranging from 4000-20000 has been carried out with SST k- turbulence model. It has been found that for the Case 1, ribs have negligible effect on heat transfer augmentation and pressure drop, unlike Case 2 where a moderate effect is observed. Maximum values for Nusselt number and friction factor are obtained for Ribs Top Fin Bottom Channel (RTFBC).

Atomic layer deposition (ALD), a gas-phase thin film deposition technique based on repeated, self-terminating gas-solid reactions, has become the method of choice in semiconductor manufacturing and many other technological areas for depositing thin conformal inorganic material layers for various applications. ALD has been discovered and developed independently, at least twice, under different names: atomic layer epitaxy (ALE) and molecular layering. ALE, dating back to 1974 in Finland, has been commonly known as the origin of ALD, while work done since the 1960s in the Soviet Union under the name "molecular layering" (and sometimes other names) has remained much less known. The virtual project on the history of ALD (VPHA) is a volunteer-based effort with open participation, set up to make the early days of ALD more transparent. In VPHA, started in July 2013, the target is to list, read and comment on all early ALD academic and patent literature up to 1986. VPHA has resulted in two essays and several presentations at international conferences. This paper, based on a poster presentation at the 16th International Conference on Atomic Layer Deposition in Dublin, Ireland, 2016, presents a recommended reading list of early ALD publications, created collectively by the VPHA participants through voting. The list contains 22 publications from Finland, Japan, Soviet Union, United Kingdom, and United States. Up to now, a balanced overview regarding the early history of ALD has been missing; the current list is an attempt to remedy this deficiency.

The Cenomanian-Turonian rocks of South Algeria (Saharan Atlas and Sahara) are widely distributed, well exposed and display beds extremely rich in ammonites and other macrofossils as well as in microfauna and forming laterally traceable horizons. They are subdivided into four ammonite zones: Neolobites vibrayeanus Zone, Nigericeras gadeni Zone, Vascoceras cauvini Zone and Pseudotissotia nigeriensis-Choffaticeras sinaiticum Zone. The Cenomanian/Turonian boundary coincides with the base of the Pseudotissotia nigeriensis-Choffaticeras sinaiticum Zone. The lower-middle Cenomanian and middle-upper Turonian are barren of ammonites.

Plusieurs techniques de dépôt de couches minces sont développées, mais leurs applications peuvent être conditionnées par des conditions opératoires ou restreintes à une surface réduite de substrat. La technique ALD ‘Atomic Layer Deposition’ est une option idéale pour effectuer des dépôts de couches minces dans des conditions de température plus douce et de contrôle d’épaisseur de couches sur des substrats de grande surface. Elle peut être utilisée pour des applications variées en comparaison aux autres techniques.

In this paper computational and experimental work is presented on the forced-air precooling process. The process is a popular method normally used to minimize the post-harvest losses and to extend the shelf-life of a wide range of horticultural produce. In the method, cold air is forced by a fan to pass through vents and then around produce packed in a crate. During the cooling process, produce exposed to high air velocities are overcooled while others exposed to low air velocities are undercooled. This non-uniformity of airflow is a major problem and it is directly related to improper vents geometries in the crates. Therefore the correct venting is necessary to achieve rapid and uniform cooling of produce. However, package strength also needs to be taken into consideration. The influence of vent shapes on the cooling uniformity can be assessed by numerical and experimental means. This study therefore provides a viable means through numerical and experimental investigation to find the effect of variation in the size and location of vents in the crate including the effects of variation of inlet velocity on the airflow and heat transfer distribution within a crate filled with spherically shaped produce such as a plum. This work is, finally, an attempt to enhance the precooling process for spherically shaped produce.

In this paper, Slepian-Bangs-type formulas for Complex Elliptically Symmetric distributed (CES) data vectors in the presence of model misspecification are provided. The basic Slepian-Bangs (SB) formula has been introduced in the array processing literature as a convenient and compact representation of the Fisher Information Matrix (FIM) for parameter estimation under (parametric) Gaussian data model. Extending recent results on this topic, in this paper, we provide a new generalization of the classical SB formula to parametric estimation problems involving non-Gaussian, heavy-tailed, CES distributed data in the presence of model misspecification. Moreover, we show that our proposed formulas encompass the special cases of the SB formula for CES distributions under perfect model specification, the SB formulas in the presence of misspecified Gaussian models, and the SB formula for the estimation of the scatter matrix of a set of CES distributed data under misspecification of the density generator.

The aim of this work is to highlight the influence of the material constructing the anode in wire-to-cylinder negative corona discharge. A numerical simulation is presented where a plasma of pure oxygen has been considered. Three materials (stainless steel, copper, aluminum) are tested. The study is carried at atmospheric pressure and for different temperatures and voltages. The numerical results show the radial distribution of ozone for each wall material. The relationship between the material and its decomposition coefficient is revealed basing on the experimental current–voltage characteristic and in which the current is used as input data.

Atomic layer deposition (ALD), a gas-phase thin film deposition technique based on repeated, self-terminating gas-solid reactions, has become the method of choice in semiconductor manufacturing and many other technological areas for depositing thin conformal inorganic material layers for various applications. ALD has been discovered and developed independently, at least twice, under different names: atomic layer epitaxy (ALE) and molecular layering. ALE, dating back to 1974 in Finland, has been commonly known as the origin of ALD, while work done since the 1960s in the Soviet Union under the name "molecular layering" (and sometimes other names) has remained much less known. The virtual project on the history of ALD (VPHA) is a volunteer-based effort with open participation, set up to make the early days of ALD more transparent. In VPHA, started in July 2013, the target is to list, read and comment on all early ALD academic and patent literature up to 1986. VPHA has resulted in two essays and several presentations at international conferences. This paper, based on a poster presentation at the 16th International Conference on Atomic Layer Deposition in Dublin, Ireland, 2016, presents a recommended reading list of early ALD publications, created collectively by the VPHA participants through voting. The list contains 22 publications from Finland, Japan, Soviet Union, United Kingdom, and United States. Up to now, a balanced overview regarding the early history of ALD has been missing; the current list is an attempt to remedy this deficiency. (C) 2016 Author(s). Funding Agencies|Finnish Centre of Excellence in Atomic Layer Deposition by Academy of Finland; COST (European Cooperation in Science and Technology) [MP1402]

Atomic layer deposition (ALD), a gas-phase thin film deposition technique based on repeated, self-terminating gas-solid reactions, has become the method of choice in semiconductor manufacturing and many other technological areas for depositing thin conformal inorganic material layers for various applications. ALD has been discovered and developed independently, at least twice, under different names: atomic layer epitaxy (ALE) and molecular layering. ALE, dating back to 1974 in Finland, has been commonly known as the origin of ALD, while work done since the 1960s in the Soviet Union under the name "molecular layering" (and sometimes other names) has remained much less known. The virtual project on the history of ALD (VPHA) is a volunteer-based effort with open participation, set up to make the early days of ALD more transparent. In VPHA, started in July 2013, the target is to list, read and comment on all early ALD academic and patent literature up to 1986. VPHA has resulted in two essays and several presentations at international conferences. This paper, based on a poster presentation at the 16th International Conference on Atomic Layer Deposition in Dublin, Ireland, 2016, presents a recommended reading list of early ALD publications, created collectively by the VPHA participants through voting. The list contains 22 publications from Finland, Japan, Soviet Union, United Kingdom, and United States. Up to now, a balanced overview regarding the early history of ALD has been missing; the current list is an attempt to remedy this deficiency. (C) 2016 Author(s).

In this paper, we address the problem of detecting a range-spread target embedded in a non-Gaussian clutter with unknown covariance matrix and without using secondary data. We propose a new autoregressive method based on the generalized likelihood ratio test (GLRT) that requires only the cells under test. This method is used to derive two new detectors, corresponding to two different scenarios: a) when all range cells contain the target and share the same covariance matrix (homogeneous clutter), b) when different covariance matrices for different range cells are assumed (heterogeneous clutter). The proposed method is shown to outperform the state of the art on various scenarios in terms of false alarm probability and detection probability, especially in critical scenario as small data records or low number of secondary data. Finally, it exhibits the desired constant false alarm rate (CFAR) property.

The purpose of this work is to highlight the chemical kinetics in plasma of pure oxygen. A comprehensive model of ozone generation in wire-to-cylinder negative corona discharge is presented. The model combines the physical processes in the discharge with the chemistry of ozone formation. It is based on an extensive reaction scheme including the major electronic and ionic processes. The importance of excited atomic and molecular states is demonstrated. The obtained results show clearly that the surface material affect quite well the ozone decomposition.

يهدف هذا البحث إلى د ا رسة ممارسات تبني حوكمة الشركات في شركات المساهمة الج ا زئرية، وذلك بالتطرق إلى مختمف المفاهيم الم ا رفقة. فقد تم التركيز عمى طبيعة النوعية المؤسساتية ودورها في خمق مناخ ملائم للإعمال، كما تم د ا رسة معايير المسؤولية الاجتماعية كآلية لتجسيد أخلاقيات الأعمال، وهذا بهدف الرفع من الأداء المؤسسي لمشركات. الد ا رسة شممت 021 شركة مساهمة عامة، تم استخدام نموذج المعادلات الهيكمية. حيث أظهرت النتائج أن حوكمة الشركات تساهم في رفع الادعاء المؤسسي، في حالة توفر نوعية مؤسساتية ملائمة للأعمال، وتبني الشركات لممسؤولية الاجتماعية.

الفصل الأول من النذكرة خصص للتعرف على أسس الحكم الرشيد و دوره في التنمية و من خلاله تم التطرق إلى مراحل نظريات التنمية و تطورها،أما الفصل الثاني فتطرق إلى مؤشر قياسه،و الفصل الثالث عالج مفهوم و أصل حوكمة الشركات و الشطر الثاني من الفصل خصص لظهور هذا المصطلح في الجزائر و حوكمة المؤسسات الصغيرة و المتوسطة في الجزائر ثم إقتراح قياس حوكمتهانعن طريق إستخدام نظرية المجموعات المبهمة.

The reported heterogenous photocatalytic sythesis of NH 3 from N 2 and H 2 O in the presence of iron-doped TiO 2 or other semiconducting metal oxides has been investigated. Skepticism about this thermodynamically and mechanistically daunting process is appropriate, and the results reported here support a skeptical position. To assess the reproducibility of the results obtained by previous workers, we performed a large number of experiments under various conditions similar to those employed with apparent success by others. We also carried out 15 N isotope labelling experiments in which the lower limit of detection was around 0.2–1 nmol of added 15 NH 3 in 10 μmol of natural ammonia, i.e. two to three orders of magnitude below the levels reported in successful syntheses by others. All the catalysts tested promoted the photo-oxidation of ammonia under the conditions said to give ammonia photosynthesis. Photocatalytic nitrogen fixation was not found in any of the experiments, although in some cases results were obtained that could have been mistaken for nitrogen fixation. Our results suggest that the reported putative reaction does not occur. We recommend that any further research in this area should be based on standards of demonstration as rigorous as those applied in experiments on the biological fixation of nitrogen.

Clinical, neurobiological and neuropsychological hypotheses suggest that the dimension of alcohol craving includes the concept of both obsessive thoughts about alcohol use and compulsive behaviors toward drinking. Anton et al. (1995) developed a 14 items self-rating scale, the Obsessive Compulsive Drinking Scale (OCDS) which includes items for assessing three dimensions: global, and the obsessive and the compulsive subdimensions. In this study, we included 156 patients, 105 men and 51 women, who met DSM IV diagnostic criteria for alcohol dependence. The mean age of our population was 39.1 +/- 11.2 years without difference between sexes. We did not found any correlation between the CAGE score and the OCDS total score or the obsessive and compulsive subscores (respectively, r = .15, r = .10 et r = .18). Moreover, we did not found any correlation between OCDS scores and mean daily alcohol consumption (r = .18, r = .16, r = .19). This could indicate that the dimension measured by the scale was somewhat independent of actual drinking. As such, it might act as an independent measure of the "state of illness" for alcohol-dependent patients. The test-retest correlation for the OCDS total score was .95 and the obsessive and compulsive subscales test-retest correlations were .93 and .89 respectively. The internal consistency of the items of the OCDS was high (alpha = .89). Principal component analysis had identified in the french version of the OCDS, three factors accounting for 63.5% of the total variance. These results indicate that the french version of the OCDS seems to validly measure a dimension of alcohol dependence. The ease of administration, reliability, and concurrent validity of the OCDS makes it particularly useful as an outcome measurement tool for various clinical therapeutic protocols in alcoholism.