The main challenge of military tactical communication systems is the accessibility of relevant information on the particular operating environment required for the determination of the waveform's ideal use. The existing propagation model focuses mainly on broadcasting and commercial wireless communication with a highs transceiver antenna that is not suitable for numerous military tactical communication systems. This paper presents a study of the path loss model related to radio propagation profile within the suburban in Kuala Lumpur. The experimental path loss modeling for VHF propagation was collected from various suburban settings for the 30-88 MHz frequency range. This experiment was highly affected by ecological factors and existing wave propagation effects such as reflection, diffraction, scattering, and Doppler effect. Radio propagation performance is evaluated by collecting received power at the allocated substation and comparing it against existing propagation models. The existing propagation model also will be tuned close to the measurement value by identifying the best path loss exponent to perform a suitable model for a suburban area. Theoretical assessments and analysis of the initial measurement stage for radio propagation show the extensive contribution of radio field from potential obstacles at lower VHF frequencies for both short and medium ranges around there. The explanation indicates the standard radio propagation prediction models that are generally reasonable for the suburban area. From the general error analysis, it is seen that, the performance of the LDPL with adjusting path loss exponent is the suitable model since it has least value of error metrics.
The design, construction and investigation of experimental study of two compound parabolic concentrators (CPCs) with tubular absorber have been presented. The performance of CPCs have been evaluated by using outdoor experimental measurements including the instantaneous thermal efficiency. The two CPCs are tested instantly by holding them on a common structure. Many tests are conducted in the present work by truncating one of them in three different levels. For each truncation the acceptance half angle (θc) was changed. Geometrically, the acceptance half angle for standard CPC is (26o). For the truncation levels for the other CPC 1, 2 and 3 the acceptance half angle were 20o, 26o and 5
... Show MoreThe effect of internal acoustic excitation on the leading-edge, separated boundary layers and the aerodynamic performance of NACA23015 cross section airfoil are examined as a function of excitation location with ranging frequency range (50-400) Hz of the introduced acoustic. Tests are separately conducted in two sections, open type wind tunnels at the Reynolds number of 3.3x105 for measurement at angle of attack (0, 3, 6, 9 &12) deg. and 3x104 for the visualization at angle of attack (12) deg. based on the airfoil chord. Results indicated that the excitation frequency and the excitation location are the key parameters to alter the flow properties and thus to improve the aerodynamic performance. The most effective excitation frequency
... Show MoreFor over a century, the global consumption of asphalt binder in asphalt mixture production has been substantial. In the Heet region (west of Iraq), two distinct forms of natural asphalt (NA) deposits exist: rock asphalt and sulfur spring asphalt. This study focused on using NA sourced from sulfur springs. The aim was to investigate the potential of incorporating NA into local asphalt mixtures. To achieve this, NA was heated to 163°C for varying durations. After heat treatment, laboratory tests were conducted on NA. The findings suggest that by heating NA for 20 hours, it conforms to Iraqi specifications in terms of physical properties. Furthermore, compared to conventional petroleum asphalt, treated NA showed greater
... Show More An experimental and computational study is conducted to analyze the thermal performance of heat sinks and to pick up more profound information in this imperative field in the electronic cooling. One important approach to improve the heat transfer on the air-side of the heat exchanger is to adjust the fin geometry. Experiments are conducted to explore the impact of the changing of diverse operational and geometrical parameters on the heat sink thermal
performance. The working fluid used is air. Operational parameters includes: air Reynolds number (from 23597 to 3848.9) and heat flux (from 3954 to 38357 W/m
2 ). Conformational parameters includes: change the direction of air flow and the area of conduct
The research attempts to diagnose the level of the effect of human resources flexibility (employees skills flexibility, employees behaviors flexibility, and human resource practice flexibility) in the south al-rusafa directorate of a power station one of the formations and the Ministry of Electricity, and impact of a range of variables related to the performance operational, namely, (efficiency, effectiveness)recognizing the importance of the subjects studied,& because of the importance of expected results of the field under consideration,researcher selected a sample of size (121) engineers and technicians of workers in the directorate. Was my hypotheses the major search of a relationship and impact between human resources flex
... Show Moreيهدف هذا البحث إلى تحليل محتوى كتابي الحاسوب للمرحلة الإعدادية في جمهورية العراق وفقاً للتفكير المنطقي، واتبعت الباحثة منهج البحث الوصفي التحليلي، وتم توظيف أداة تحليل المحتوى، التي صُمِّمت وفقاً للعمليات العقلية المتضمنة في التفكير المنطقي بحسب العالم بياجيه ( Piaget )، واعتماد وحدة الفكرة (الصريحة) في عملية التحليل. تبين من نتائج هذا البحث أنَّ نسبة تضمين مهارات التفكير المنطقي في محتوى كتابي الحاسوب للمرحل
... Show MoreEnglish ابحث عن مقالات و مجلات ... تحليل علاقة ثقافة المنظمة بلازمة من منظور الفردبة - الجماعية أ.د زكـريا مطلك الدوري، أ.د سـعـد علي العـنزي، أ. يعرب عدنان السعيدي مجلة كلية بغداد للعلوم الاقتصادية الجامعة 2009, المجلد 2, العدد 20, الصفحات 107-122 الخلاصة تتعدد وجهات النظر بشأن الاسباب والمعالجات الممكنة للازمات، وان هذا الاختلاف يرجع بالاصل إلى تنوع المداخل التي يعتمد عليها الباحثين في تناول الظاهرة أو الموضوع. وضمن هذا
... Show Moreيهدف هذا البحث إلى تحليل محتوى كتابي الحاسوب للمرحلة المتوسطة في العراق وفقاً لعمليات العلم عن طريق الإجابة عن السؤال الآتي: ما نسبة توافر عمليات العلم في محتوى كتابي الحاسوب المقرران على طلبة المرحلة المتوسطة المعتمدان من وزارة التربية العراقية/ المديرية العامة للمناهج في العام الدراسي ( 2016-2017) م؟ اعتمد هذا البحث المنهج الوصفي التحليلي، وتضمن مجتمع البحث وعينته محتوى كتابي الحاسوب المقررين لطلبة الصفين
... Show MoreTurkman literature is regarded as a branch of the general Turkish literarure. The title Turman literature began to be used after 1918, and this remained under the influence of classical Turkishliterature till the beginning of the twentieth century. The best poets who repreesented this type are Hijri Dada, Khidir Lütfi, Mohammad Sadiq, Othman Mathloom and others…
In this study I followed the method of Professor Doctor Mohammad Kaplan (Ph.D) and Professor Doctor Nurullah Çetin(Ph.D) in analysing the poetical design. In this study I tried to analyse the poem entitled Taliim (My Fate) by the poet Khidir Lütfi and the poet Othman mathloom who wrote a poem wi
... Show More