Circulation pattern of the Egyptian Mediterranean waters during winter and summer seasons

The water circulation of the Egyptian Mediterranean waters was computed during winter and summer seasons using the dynamic method. The reference level was set at the 1000db surface. The results showed that the surface circulation is dominated by the Atlantic water inflow along the North African coast and by two major gyres, the Mersa Matruth anticyclonic gyre and El-Arish cyclonic gyre. The results showed a seasonal reversal of El-Arish gyre, being cyclonic in winter and anticyclonic in summer. El-Arish gyre had not been previously measured. The geostrophic current velocity at the edges of the Mersa Matruth gyre varied between 12.5 and 29.1cm/sec in winter and between 6.5 and 13.1cm/sec in summer. The current velocity reached its maximum values (>40cm/sec) at El-Arish gyre. The current velocity at the two gyres decreased with increasing depth. The North African Current affects the surface waters down to a depth of 100m, and that its mean velocity varies between 6 and 38cm/sec

A systematic approach to atomicity decomposition in Event-B

Event-B is a state-based formal method that supports a refinement process in which an abstract model is elaborated towards an implementation in a step-wise manner. One weakness of Event-B is that control flow between events is typically modelled implicitly via variables and event guards. While this fits well with Event-B refinement, it can make models involving sequencing of events more difficult to specify and understand than if control flow was explicitly specified. New events may be introduced in Event-B refinement and these are often used to decompose the atomicity of an abstract event into a series of steps. A second weakness of Event-B is that there is no explicit link between such new events that represent a step in the decomposition of atomicity and the abstract event to which they contribute. To address these weaknesses, atomicity decomposition diagrams support the explicit modelling of control flow and refinement relationships for new events. In previous work,the atomicity decomposition approach has been evaluated manually in the development of two large case studies, a multi media protocol and a spacecraft sub-system. The evaluation results helped us to develop a systematic definition of the atomicity decomposition approach, and to develop a tool supporting the approach. In this paper we outline this systematic definition of the approach, the tool that supports it and evaluate the contribution that the tool makes

A New Equivalent Circuit of a Salient-Pole Synchronous Machine and Its Phasor Interpretation

This paper examines a shortcoming of the classical phasor diagram of a salient-pole synchronous machine based on the well-established two-reaction theory. Unlike in the phasor diagram of a smooth-air-gap machine, it is not possible to readily identify the internally-developed electromagnetic power of a salient-pole synchronous machine from this phasor diagram. By defining new machine reactances, a single equivalent circuit of a salient-pole synchronous machine is proposed together with a phasor diagram where the internally-developed electromagnetic power is made apparent. The revised two-reaction theory is illustrated using the mathematical model of a two-phase salient-pole synchronous machine whose equations are manipulated using complex space vectors instead of traditional matrix transformations

Logic Algorithm for contour following task: An evaluation using Adept SCARA Robot

This paper presents the performance evaluation of logic algorithms for contourfollowing task in order to automate the manual programming process. The main objective of this work is to evaluate and compare the performance of single logic and dual sensor logic algorithmsfor autonomous contourfollowing in industrial robot. Thosi atgorithms have been implemented using Adept SCAM robot. The algorithms were tested on a semicircle object o/ 40 millimeter radius. The result shows mean of error and standard deviation value of single logic algorithm is a bit lower than clual sensar logic algorithtn

Heritage language learners of English: Linguistic gaps and cognitive strengths

Purpose: This study examined whether Heritage Language Learners (HLLs) of English display profile effects in their performance on knowledge- and processing-dependent measures relative to the standardised mean scores of monolingual speakers. The study also investigated the influence of several experiential factors on HLL performance. Method: Participants were 59 Arabic-speaking HLLs from six to nine years old. The children completed a battery of linguistic tests in their L1 and L2, as well as cognitive measures of short-term and working memory and non-verbal intelligence. Result: Significantly lower standardised scores were observed for HLLs as compared to the standardised mean scores on all Arabic/English language tasks except L2 word reading. HLLs scored at or above age-level expectations on cognitive measures except the Arabic nonword repetition task. Stepwise regression analyses examining variance in HLLs\u27 performance, age and richness of environment consistently explained HLLs\u27 performance in L1 Arabic, but different factors accounted for HLLs\u27 performance in English depending on the task. Age was the only variable that consistently explained variance in performance on the cognitive measures. Conclusion: The results suggest that processing-dependent measures may be less sensitive to difference in language experience than traditional knowledge-based measures such as standardised measures of language and vocabulary

Isolation and Identification of Phenol-Degrading Bacteria from Oil-Contaminated Sites

This work is aimed at isolating and identifying phenol-degrading bacteria from oil-contaminated sites. Five soil samples from three auto-mechanic workshops within Katsina metropolis were collected. The samples were analyzed by selective enrichment technique, which resulted in the isolation of four bacterial species. The species were further subjected to the Vitek 2 compact microbiological system analysis. Cupriavidus pauculus, Pontoea spp, Proteus mirabilis 1 and Proteus mirabilis 2 were identified. Result from the present study showed that the bacteria could utilize phenol as their carbon source. Proteus mirabilis 1 and Proteus mirabilis 2 showed lower phenol degradation potential, under similar conditions. Cupriavidus pauculus and Pontoea sp. showed significant increases (p<0.05) in their optical densities. The optical density increment is strongly correlated with increase in colony forming units of the bacteria. This study further showed that the isolates could tolerate high phenol concentrations and may serve as strong putative isolates in bioremediation of phenol-contaminated sites

Generation of three-qubit entangled states using coupled multi-quantum dots

We discuss a mechanism for generating a maximum entangled state (GHZ) in a coupled quantum dots system, based on analytical techniques. The reliable generation of such states is crucial for implementing solid-state based quantum information schemes. The signature originates from a remarkably weak field pulse or a far off-resonance effects which could be implemented using technology that is currently being developed. The results are illustrated with an application to a specific wide-gap semiconductor quantum dots system, like Zinc Selenide (ZnSe) based quantum dots.Comment: 8 pages, 2 figure

Distribusi Unsur Hara N dan P dalam Sedimen di Ekosistem Lamun (Seagrass) di Wilayah Pesisir Desa Kabonga Besar Kabupaten Donggala

This research aims to determine the distribution patterns and concentrations of nitrogen and phosphorus nutrients in the sediment at the coastal region of seagrass ecosystems Kabonga Besar village Donggala district. Phosphorus (P) and nitrogen (N) in water its are nutrient that is essential for the growth of phytoplankton. This research was carried out by quantitative analysis using a nitrogen compound Kjeldhal method which consists of three phases: destruction, distillation, and titration, while for phosphorus compound using UV-Vis spectrophotometric method. The results showed that the lowest levels of nitrogen were obtained at the level of fertility sea grass sediments are less abundant range of 0.05% - 0.06% , on the contrary sea grass abundant fertility rate which ranges from 0.07% - 0.09%. For the highest levels of phosphorus nutrients contained in the water that is abundant on sea grass fertility ranged from 4.335 - 4.387 mg/100, and the lowest was ranged from 2.292 - 2.358 mg/100. Based on the data obtained it can be concluded that the content of nitrogen and phosphorus nutrients in sediments sea grass at the research area was still relatively low, it could affect the growth of seagrass

Follow-up And Kinetic Model Selection Of Dinitro Pentamethylene Tetramine (DPT)

The Synthetic route of Cyclotetramethylene Tetramine is implemented through the reaction of hexamine and nitrating mixture that is formed as a result of a reaction between ammonium nitrate and fuming nitric acid. The reaction medium includes acetic acid, acetic anhydride and p-formaldehyde. This synthetic pathway is relatively long and both of hexamine dinitrate and Dinitro Pentamethylene Tetramine (DPT) are considered as the two main intermediate compounds. The former compound (hexamine dinitrate) was prepared, purified, and then characterized. Conversion of hexamine dinitrate into DPT has been followed up experimentally at different temperatures. Various factors including temperature and time has been investigated. The obtained results were reliable and consistent with the literature. Different kinetic models have been tested. The unreacted core model proved to be applicable, and the surface reaction was found to be controlling