تعیین تابع توزیع احتمال چگالی نوری در فیلم‌های رادیوگرافی صنعتی با پرتو ایکس

نوع مقاله: مقاله پژوهشی

نویسندگان

پژوهشکده‌ی کاربرد پرتوها، پژوهشگاه علوم و فنون هسته‌ای، سازمان انرژی اتمی ایران

چکیده

در این مقاله به بررسی تابع توزیع چگالی نوری حاصل از فیلم­ رادیوگرافی در ولتاژهای 80 الی kV 120 پرداخته شده است. صفحات فولادیcm2 30×30 به ضخامت‌­های 2 و mm 8 براساس استانداردهای اروپایی با شدت جریا­ن­‌ها و زمان­‌های مختلف تحت تابش قرار گرفته­‌اند. اطلاعات فیلم­‌های رادیوگرافی با اسکنر لیزری به داده­‌های عددی بر مبنای داده­‌های 8 بیتی با قدرت تفکیک dpi 3200 تبدیل شده­‌اند. هیستوگرام‌­های حاصل از این اسکن­‌ها با تمام توابع احتمال موجود مقایسه شده‌­اند. به علت فراوانی توابع احتمال، ابتدا میزان انطباق آن‌ها بر بهترین و ساده­‌ترین هیستوگرام بررسی شد. سپس توابع انتخاب شده برای فیلم­‌های باقی­‌مانده به­‌کار رفتند. به این ترتیب بهترین تابع توزیع احتمال مشخص شد. همین مراحل برای عیوب رادیوگرافی نیز به اجرا درآمدند. هم­چنین میزان انطباق توابع توزیع احتمال به کار برده شده برای حالت زمینه و عیوب نیز بررسی شد.

کلیدواژه‌ها


عنوان مقاله [English]

Determination of Probability Distribution Function of Optical Density in Industrial Radiographic Films by X-Ray

نویسندگان [English]

  • M. T Sasanpour
  • A Taheri
  • R. G Peyvandi
چکیده [English]

In this paper, the optical density distribution function obtained from the radiographic films at the voltages of 80-150 kV was investigated. Steel plates of 30×30 mm2 with thicknesses of 2 and 8 mm were irradiated according to the European standards with different currents at various times. The information of the radiographic films was converted into 8-bit numeric data by using a laser scanner with a resolution of 3200 dpi. The histograms obtained from these scans were compared with all applicable probability functions. Due to the large number of the employed probability functions, their compatibility was first assessed on the best and simplest histogram. Afterwards, the selected functions were used for the remaining films. In this way, the best probability distribution function was determined. The same steps were taken for radiographic defects. Furthermore, the degree of adaptation of the probability distribution functions applied to the base metal and the defects regions was also evaluated.

کلیدواژه‌ها [English]

  • Radiographic Film
  • X-Ray
  • Probability Distribution Function
  • Histogram
  • Radiography
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