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dynamic coloring of graph
در این پایان نامه رنگ آمیزی دینامیکی یک گراف را بیان و مطالعه می کنیم. یک –kرنگ آمیزی سره ی رأسی گراف g را رنگ آمیزی دینامیکی می نامند اگر در همسایه های هر رأس v?v(g) با درجه ی حداقل 2، حداقل 2 رنگ متفاوت ظاهر شوند. کوچکترین عدد صحیح k، به طوری که g دارای –kرنگ آمیزی دینامیکی باشد را عدد رنگی دینامیکی g می نامند و آنرا با نماد ?_2 (g) نمایش می دهند. مونت گمری حدس زده است که تمام گراف های منتظم ...
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Perfusion lung imaging for diagnosing pulmonary embolism (PE) was introduced 50 y ago (1). At that time, it offered a noninvasive alternative to pulmonary angiography in patients with a clinical suspicion of PE. Because there are many causes of diminished regional blood flow in the lungs, particularly redistribution of blood flow away from regions with lung disease, the subsequent introduction ...
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This study explores the assumption that 81mKr static images represent regional ventilation. Dynamic acquisition of 81mKr ventilation images permits creation of time-activity curves and the possible separation of the confounding influences of ventilation and volume. By using a two-compartment gas mixing lung phantom, the results demonstrate that both total and tidal 81mKr are closely related to ...
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Pulmonary embolism (PE) is a preventable cause of morbidity and mortality which needs prompt recognition. Ventilation-perfusion (V/Q) scan is a well-established diagnostic test for evaluation of suspected PE. We report a 32-year-old woman with history of rheumatologic disease and acute dyspnea, who was referred for V/Q scintigraphy. The planar images revealed multiple mismatched defects through...
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ژورنال
عنوان ژورنال: Acta Radiologica
سال: 1991
ISSN: 0284-1851,1600-0455
DOI: 10.3109/02841859109177526