DICOM example error

Dear experts

I tried to build dicom example with DICOM_USE_DCMTK, DICOM_USE_HEAD,DICOM_DIR and I complete. But I can’t execute ./DICOM because of the RAM(16GB in my laptop) and I set the number of thread to 8 but only work 1.
Is it just my computer problem? I want to change example dicom file to mine but I’m already blocked because of this problem. help me…