This work describes the architecture and design of an onboard digital receiver of the phase radio-navigation system for aircraft blind landing proposed in [1]. The proposed onboard digital receiver is a special case of a multi-channel narrowband digital receiver concept. The purpose of this receiver is to receive eight different RF frequencies (in four pairs) range from 960 MHz to 963.003749941 MHz, carry on them the required analogue and digital signal processing techniques to evaluate their phase shifts and then the difference phase shifts between each pair of them. The phase measurements lead to determination of the location of the aircraft with respect to the touch point on the runway with accuracy in millimetres.

This paper presents the findings of the investigation of ERP implementation. It highlights the challenges and experiences of Libyan Companies in ERP implementation. The success factors, failures are analyzed and have proposed recommendations to improve ERP implementation. The adopted research approach covers both quantitative and qualitative methods. The data collection methods used were questionnaires, 75 out of 100 questionnaires were returned sufficiently completed. The paper contributes to discussion based on literature review and ERP implementation in developing economics. The results of the study revealed that the majority of the respondents are aware of what ERP is all about, and they are also aware about critical issues in the implementation of ERP. The findings revealed that: failure to select committees needed for the successful implementation of ERP, an inadequate financial budget and resources, and failure to make knowledgeable input at the planning stage can be problems to successful implementation of ERP. The conclusions suggest for addressing challenges and problems in the ERP implementation. Enough time should be provided to project team, show leadership in change management and sufficient resources should be allocated for the proper implementation of ERP.

In this work, the estimation capacity of the response surface methodology (RSM), in the catalytic naphtha reforming to enhance the octane number of reformats via isomerization reaction pathway and minimize the aromatization activity over tri-metallic modified Pt-Re/Al2O3 catalyst were investigated by applying Design of experiment (DOE). The parent bimetallic catalysts were modified using a relatively inactive metal (Sn) by means of employing non-conventional method of anchoring technique called controlled surface reaction (CSR) method in order to favor the intimate contact of Sn with the active phase to suppress the metallic character of Pt metal. The correlations between RON, aromatization and isomerization activities with three reaction variables namely temperature (480-510oC), pressure (10-30 bar) and space velocity LHSV (1.2-1.8 h-1) were presented as empirical mathematical models via reforming of a complex mixture (80oC -185oC). Numerical results indicated that the minimum aromatization activity was 20% when reaction temperature was 460oC and pressure of 35 bar. Results also show that maximum isomerization activity of 58% was achieved when pressure is 30 bar and space velocity is 1.8 h. it has been found that optimum value of RON = 89 was attained at 449.9oC, 32 bar and 1.7 h-1. However, high operating pressure and low reaction temperature significantly decrease the aromatization activity coupled with substantial decrease in RON which can be enhanced by producing high yield of isomers.  

The effect of a relatively inactive metal on the texture properties and catalytic performance of bi-metallic platinum–rhenium (Pt–Re)–S/Al2O3–Cl catalyst was investigated. The concentration of introduced tin (Sn) varied between 0.06 and 0.32 % (weight basis). The parent and modified catalysts were characterized using the following techniques; BET, X-ray diffraction, SEM–EDX, and atomic absorption spectroscopy/inductively coupled plasma spectroscopy. The bi-metallic and tri-metallic catalysts were also screened for their activity and selectivity in the reforming of n-octane under the following conditions: T = 480 °C, p = 10 bar, WHSV = 3.3 h⁻¹ and H2:HC = 4.5. Results showed that, on n-octane conversion, selectivity have changed favorably i.e., low selectivity to aromatics but high selectivity to iso-paraffins and olefins. In addition, less cracking products were detected and high liquid yields (LYs) were obtained. However, there is a strong and closely linear correlation between aromatics and octane number. The results of this work showed that catalyst with Sn >0.14 and <0.32 performed the best catalyst i.e., no major effect on research octane number, LY and selectivity with the addition of more Sn.

( حول جدلية العلاقة بين زمن اللفظ وزمن التلفظ )

يُعرّف عالم اللغة الشهير فرديناند دي سوسير اللغة بأنها متوالية من الدلائل اللغوية التي وضعها الهيكل الاجتماعي ليسمح باختيار أو استخدام ملكة الكلام لدى الأفراد ، ولها معاييرها المحددة ، ولهذه المتوالية الصوتية المرسلة بدايتها ونهايتها تتحدد بفترة الصمت المؤقت بين متوالية صغيرة منها مجموعة الجمل والكلمات . أما التلفظ أو التكلم أو الأداء فهو الطريقة الفردية الخاصة لاستعمال اللغة ، في حين أن الحديث هو نتيجة هذه العملية ، وعملية التلفظ هذه تحركها هي الأخرى مجموعة من العوامل تكون سببا في النهاية لوجود الحديث الذي يمكن أن يكون نحويا أو دلاليا ، فمجموعة الأحاديث تشكل عينة لغوية قائمة على مجموعة من الجمل المبنية على قواعد ، وفي اللسانيات يطلق المصطلح على جزء من المنظومة الكلامية طولها يتحدد بعلامات الترقيم كالفاصلة والنقطة ... الخ . ولقد تناولت الدراسات اللغوية العلاقة الجدلية بين اللفظ والتلفظ والتي أخذت مسميات ومستويات شتى في التحليل نظرا لتناولها من زوايا مختلفة ورؤى متباينة نظرا لتشعب الموضوع وارتباطه مباشرة بالمحيط اللغوي والاجتماعي المتغير بطبيعته ، وهو ما حدا بكل تلك الدراسات الى اعتبار العلاقة جدلية ضمن الفضاء العام للتواصل بين اللفظ والتلفظ وبين الجملة والملفوظ وتعلق فعل الملفوظ بفعل التلفظ وهكذا .  

Introduction

L'énoncé est l'objet produit, réalisé et engendré par le processus d'énonciation . Un morphème, un syntagme, une proposition, une phrase, un ensemble de phrases et un texte achevé peuvent constituer un énoncé. L'énonciation est - telle que E. Benveniste l'a défini " cette mise en fonctionnement de la langue par un acte individuel d'utilisation". Il va jusqu'à dire que " l'acte même de produire un énoncé "( E. Benveniste,1970: 12),). L'acte d'énonciation est le fait du locuteur qui mobilise la langue pour son compte. Aussi pour Anscombre et Ducrot(1970:12) : "L'énonciation sera l'activité langagière exercée par celui qui parle au moment où il parle". L'énonciation est donc par essence historique, événementielle, et , comme telle, ne se reproduit jamais deux fois identique à elle-même.C.K ORECCHIONI propose au terme « énonciation » deux glissements sémantiques. Le premier consiste à dégager le produit de l’acte de production. L’énonciation sera donc dans ce cas, l’acte de production d’un énoncé. Elle a dit à ce propos « À l’origine l’énonciation s’oppose à l’énoncé comme un acte à son produit, un processus dynamique à son résultat statique »(Ibid.1999:33). Elle propose dans le second glissement une idée qui est l’énonciation est l’action centrée sur celui qui exerce l’acte, sans négliger l’aspect communicationnel qui est fortement présent et qui s’établie entre deux partenaires, dans la mesure où le locuteur implique l’autre, alors qu’il n’est pas vraiment l’élément principal sur lequel l’énonciation fonde ses principes.

L'énonciation suppose selon E. Benveniste la conversion  individuelle de la langue en discours. Toute communication se passe dans un espace - temps déterminé, qui peut être contraignant, en ce sens qu'il exerce une influence déterminante sur le langage utilisé, ou non contraignant si le choix des moyens linguistiques n'est pas conditionné par les conditions spatio-temporelles du message.

Abstract: Monitoring the concentrations of heavy metals in natural and waste water at and below the level of their maximum permissible concentrations is an urgent environmental problem. Hence, new procedures for the preconcentration of heavy metals with their subsequent determination by different methods are required. Along with other sorbents, significant attention is attracted to polymer chelating sorbents, which provide individual or group extraction of trace elements, eliminate matrix effects, and provide high concentration factors. The effect of the various parameters such as electrochemically and chemically synthesis methods, physical oxidation state of the polymer, polymer thickness, solution pH and metal ion concentration on the adsorption, kinetics and efficiency were investigated. The results showed a vary broad concentration range of the heavy metals from (0.05 to 10 mg/L) can be adsorbed on different kinds of polymers at different pH values and different efficiently. The adsorption capacity of the polymer to different concentrations of heavy metals was evaluated as the milligram of metal ions by one gram of various forms of the polymer. The DC conductivity measurements were also employed on the solid polymer before and after adsorption of metal ions. The experimental adsorption date was fitted to different mathematical isotherms to estimate the binding constant of heavy metals with the polymer in both single and mixed ion solutions. The method provides the extraction of analytes from natural water of complex composition containing high concentrations of alkali, alkaline-earth and other elements and is characterized by rapidly, selectivity, low detection limits, and a high reproducibility of the results. The relative standard deviation is 2-4%. The technique was test with real waste water samples.  

Usually fin represent as one of the important structures in all type of airplane and the fin structure was greatly improved, especially for modern supersonic speed constructions. The main aim of delta fin construction is to minimize the weight of structure as much as possible and keeping the stiffness of material structural in margin of safety under design load [1]. The primary difference between classical method and finite element are the view structure and the ensuring solution procedure. Classical method considers the structure as a continuum whose behavior is governed by partial or ordinary differential equations [2]. By using finite element method consider the structure to be an assembly of small finite-sized particles. The behavior of the particles and the overall structure is obtained by formulating a system of algebraic equation that can be readily solved by developed methodology, which will be presented in form of software.

This work is focused on nucleation stages during isothermal austenite transformation in two types of Vanadium micro-alloyed steels. Isothermal treatment was carried out in the temperature range 350 to 600οC. Metallographic evaluation using optical and scanning electron microscopy (SEM) enabled determination of the nucleation curves of isothermally decomposed austenite. Three curves are found to be relevant to this initiation stage of transformation: first curve is related to grain boundary nucleated ferrite (GBF), second curve is related to intra-granularly nucleated ferrite (IGF) and the third to pearlite (P) curve. GBF and IGF curves are divided into two regions, which represents the high temperature and the low temperature segments as consequence of either displacive nature of transformation or diffusion transformation. Addition of Ti to V – micro-alloyed steel in this work seems to be balanced by a slightly higher C and Mn content, leading to limited effect on nucleation stage of austenite decomposition.