Continuum analysis of rarefaction effects on a thermally-induced gas flow

A Maxwell gas confined within a micro cavity with non-isothermal walls is investigated in the slip and early transition regimes using the classical and extended continuum theories. The vertical sides of the cavity are kept at the uniform and environmental temperature T_0, while the upper and bottom ones are linearly heated in opposite directions from the cold value T_0 to the hot oneT_H. The gas flow is, therefore, induced only by the temperature gradient created along the longitudinal walls. The problem is treated from a macroscopic point of view by solving numerically the so-called regularized 13-moment equations (R13) recently developed as an extension of Grad 13-moments theory to the third order of the Knudsen number powers in the Chapman-Enskog expansion. The gas macroscopic properties obtained by this method are compared with the classical continuum theory results (NSF) using the first and second order of velocity slip and temperature jump boundary conditions. The gas flow behavior is studied as a function of the Knudsen number (Kn), nonlinear effects, for different heating ratesT_0/T_H . The micro cavity aspect ratio effect is also evaluated on the flow fields in this study.Comment: 18,9 figures, submitted to Mathematical Problems in Engineering Journa

Synthesis of 1,4-Disubstituted Mono and Bis-triazolocarbo-acyclonucleoside Analogues of 9-(4-Hydroxybutyl)guanine by Cu(I)-Catalyzed Click Azide-Alkyne Cycloaddition

A series of novel mono-1,2,3-triazole and bis-1,2,3-triazole acyclonucleoside analogues of 9-(4-hydroxybutyl)guanine was prepared via copper(I)-catalyzed 1,3-dipolar cycloaddition of N-9 propargylpurine, N-1-propargylpyrimidines/as-triazine with the azido-pseudo-sugar 4-azidobutylacetate under solvent-free microwave conditions, followed by treatment with K2CO3/MeOH, or NH3/MeOH. All compounds studied in this work were screened for their antiviral activities [against human rhinovirus (HRV) and hepatitis C virus (HCV)] and antibacterial activities against a series of Gram positive and negative bacteria

Exploring tourism development on uninhabited islands

Travel Industry has become the bread winner of many Island destinations across the globe. The practices, policies and institutional forms used in developing tourism on public lands vary from destination to destination. The research aims to identify the practices, policies and institutional forms in development of tourism consisting of resorts or hotels in public lands specifically on uninhabited islands. Public lands referred in this thesis include lands, beaches, sea owned by governments or the \u27public sector\u27. The term \u27public sector\u27 covers the whole range of public organizations from national government ministries and departments to government business enterprises and local government tourism departments (Elliott, 1997). The countries studied in this research belong to the Small Island Developing States (SIDS) as categorized by United Nations Economic and Social Affairs. The increase demand for uninhabited islands has lead to change in the conventional land use rights and management of public land in previously unstructured communities in island nations. According to Hall & Page (1996) there are complicated land ownership traditions in which land is owned communally rather than by individuals and in which land is held in trust to be used to sustain a community group or tribe rather than commodity to be traded. Hence, to optimize the positive influence of resort and hotel development in island nations it is important to identify the changing practices, policies and institutional forms in island nations

Effective Cost of Brain Drain

In developing countries, remittances and intra-family private transfers sent by household members who migrate to more developed countries constitute a fundamental source of income and capital accumulation. Then, it is important to understand the motives of migrants who decide to remit back to their families. Drawing on the theory of labor migration under asymmetric information, we show that low-skilled workers are expected to provide higher amounts of remittances when remittances are motivated by self-interest. This transfer paradox is explained as follows. Since low skilled workers are likely to return home when informational symmetry is restored, the optimal remittance level is a decreasing function of the migrant's skill level since remittances may be seen as an implicit insurance, whose benefits are received only under migration return.Remittances, asymmetric information, migration

Impact of English Orthography on Learning English Sounds and Spelling

In order to learn or study English as a foreign language, the learner must be aware of pronunciation skills besides other skills which are of great importance for studying it. In Sudan, there is a large number of people who are interested in learning English as a foreign language. Among them are the students of English language at the University of Gezira. Many studies have demonstrated that the errors made by the speakers of other language who speak English, are systematic rather than random. For instance, scholars and linguists demonstrated that Arab learners of English face problems in pronunciation of sound which they are not familiar with. The present study is limited to the University of Gezira, Faculty of Education – Hassahisa English Department, students during the academic year 2015-2016 and the teachers who teach at University of Gezira-Faculty of Education Hantoub-English Department. The researcher followed the analytical descriptive method to carry out the study. The tools used by the researcher were i) a test for students of 3rd Semester at the University of Gezira, Faculty of Education, Hassahiesa ii) a questionnaire for teachers at University of Gezira, Faculty of Education-Hantoub. Correct pronunciation and spelling have been always a great challenge for the EFL learners. The present research is at attempt to find that how English orthography affects the learning of English sounds and spelling. Moreover, the research may benefit syllabus designers as well as English students who are specialized in the field of English Language by providing lights and hints in the scope of how to write in correct spelling. Keywords: orthography, pronunciation, EFL, University of Gezira, descriptive metho

Système financier marocain vers l’inclusion financière : analyse et recommandations

Le Maroc s’est inscrit durant les deux dernières décennies dans un processus continu de modernisation de son secteur financier afin d’accroître son efficacité, d’accompagner et de soutenir le développement économique et social du pays, et d’améliorer son attractivité sur le plan international. En plus, les autorités marocaines ont mis en place plusieurs réformes visant de doter le pays d’un système à même de mobiliser l’épargne de manière efficace et de l’allouer avec efficience au financement de l’économie. Récemment, l’orientation des décideurs politiques est passée du développement financier à l’inclusion financière pour favoriser une croissance économique durable. Bien que le sujet ait fait l’objet de peu d’études théoriques et empiriques, la plupart des travaux existants montrent cependant le rôle déterminant de l’inclusion financière dans le développement économique d’un pays. L’objectif de notre article est d’étudier l’évolution du système financier marocain, d’une part, citer les politiques adoptées par les autorités marocaines pour développer le secteur financier et, d’autre part, d’analyser la stratégie l’inclusion financière au Maroc comme levier du développement économique

Optimal Level of Participatory Approach in an NGO Development Project

Many authors, Bradley (2006), Banerjee (2007), Mohan (2008) and Sen (1999) among others, argue that the participatory approach in the development projects of a non-governmental organization, NGO, is more effective and sustainable than the externally imposed expert-driven approach. According to this research stream, the participatory approach promotes self-respect, dignity, inclusiveness, and empowerment of people involved in the project and, simultaneously, it improves the external local environment for the NGO. The key point of this paper is that adopting only the participatory approach may not be optimal, as this approach involves costs to learn about local culture, values and attitudes, and to design and implement feasible participatory development practices. Accordingly, an economically sensible and sustainable strategy for the NGO will be to use a mixture of both approaches. In this paper, the optimal level of participatory approach is theoretically derived and numerically illustrated

Étude Lithostratigraphique Des Formations Superficielles Urbaines Du Secteur Nord De La Ville De Fès, Maroc

The superficial formations of the northern sector of the city of Fez majorly show clay lithostratigraphy in the west of this sector. They are conglomeratic at the center and are composed of limestone deposits in the East. As for the land embankments, they met at two banks of Oued Fès. From a geotechnical point of view, the formations which are exposed to the phenomena of compressing or liquefaction are the argillaceous and anthropic formations. These phenomena of the instability of the grounds can worsen when the water table level increases significantly, especially during the rainy seasons where it can reach the surface at the Oued Fez flood plain. As for the conglomeratic formations, the geotechnical analysis shows that the conglomerates forming a very hard rocky slab constitute a rather solid base and is indeformable. Their thickness, therefore, exceeds 2m of power. This is the case of conglomerates located at the center of this sector. Laboratory tests have classified these soils to be relatively stable