Abstract
An optoelectronic system for fog detection and visibility technique is presented .The idea of this research is based on the measurement of the atmospheric visibility by using an infrared beam emitter from LED diode. The optical scattering is used as a method to calculate the visibility. This method is applied at forward scattering within a foggy atmosphere, which is modern and has great importance for measuring visibility in seaports, airports, public roads and highways. In this paper we focus on the description of the system, principles of its operation and some results of field tests.
Keywords: fog sensor, visibility sensor, backscattering, forward scattering.
جاء هذا البحث في اربع مباحث تناول المبحث الاول الاطار العام للبحث ،وتناول المبحث الثاني (الدراسة النظرية) بيان تاريخ المعجمات اللغوية والتعريف بها وباهدافها ووظائفها وانواعها والمادة التي تناولتها وتنظيمها وترتيبها ،وتناول المبحث الثالث(الدراسة العملية) التعريف بالمعجمات اللغوية الورقية والمحوسبة المتوافرة في مكتبات عينة البحث وبيان مدى استعمالها من طلبة الدراسات العليا ، وتناول المبحث الرابع الاستنتاج
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